Now get your butt out there and build yourself an engine young fellah. You kids these days, they just dont do anything unless someone is there to push them.
I've been watching videos on RUclips since it began. I can say, with 100% certainty, that this is the most well thought out, perfectly executed, easy to understand, vastly informative, instructional, and motivational video I've seen to date. You rock dude. Dead serious. Thank you very much!
you had me until your 4800 pounds of spring pressure, that's not how that works. you don't have constant pressure on every spring. aside from that, good video.
@@Doing_it_right_the_first_time It's a good introduction, but as with everything you gotta look around a bit before you draw conclusions. I've learned that if you really want good information, you should just buy a book. Haha maybe youtube should bring back the 5 star rating system they had back in the day.
This is information that the old timers kept secret when I was a kid. I had the fundamentals of how this worked before, but these essential details are priceless. I've been building engines here and there since I was 16, so 27 years. I have come close but having known this I could have nailed it so much easier than assembling, driving, adjusting, deciding to swap or modify parts to get what I wanted out of the engine, on and on... I used to try to get help like this from my step Dad, my Uncles, etc...they would NEVER tell me about this stuff. Thank you SO much for this. I'm working on an old 350 in my square body right now and will be utilizing this info and rewatching this many times. More upsetting is knowing that people I asked KNEW this and just treated me like I was stupid because I didn't know what I didn't know. I knew I was missing something and this was it - the MATH. SUBBED - thanks again!
A cam was called a 3/4 rumpty dump cam...hahaha. then I moved to Florida. Lol, they're calling out durations and had ceramic clutch plates. Wow. Things have changes a bunch, with computers.
@@KingJT80 negative his theory is every camshaft is a turbo camshaft (Aftermarket). There is way more explanation and science that is involved. Hint this video.
@@rafatrill yes it matters more when you're trying to RACE but as far as a turbo specific cam thats more of a racers edge that a street guy wouldnt really need as much and yes richard did mention that
@@KingJT80 why do u think we watch his videos to have the edge when someone wants the smoke on and off the track. That's like saying a street guy isn't a racer or doesn't go to the track once in his life
I'm glad you couldn't find a explanatory video on camshaft selection. You did an excellent job. I even took notes. Thank you for taking the time, you helped a lot of people.
Great informative video. Just one note....not all springs are being compressed at max simultaneously. Total combined spring pressure cant be 7,200lbs as pressure varies for each position on the cam lobe. I would assume its closer to about 1,500-2,500 lbs of combined constant pressure.
That’s what I was thinking, and wondering if the release of spring pressure helps push the cam/crank, and relieve some of that pressure while some springs are on the beginning of the cam lobe rise and some are on the fall of the cam lobe
The pressure after the cam reaches the top would be pushing down on the opposite side of the cam. Wouldn't this cancel the power lost on the opening of the valves? Regardless, this is a great video. 👍
This is hands down the best channel on RUclips related to engine building. I’ve learned a lot but more importantly it’s helped me do all my own work and build my motor
Hence why there's only 90k subs.... A majority of the auto enthusiast community "wish" they had what it takes but only about 10% have the capacity to actually learn and retain information to be dominant in their platforms.
I thought I knew how to pick a cam based on intended use. I never realized about matching cylinder head flow to cam lift. After watching this I went and found the flow sheet for the cylinder heads on the 383 I'm building. I was going to install higher ratio rockers for more lift but decided that stock ratio with the springs I installed might offer a little more engine life. It turns out that the cam that I accidently stumbled upon matches my cylinder heads perfectly as he described. Thanks for another great vid. Totally made my day! Lol
Something told me to have my notebook ready...glad I listened to "something" and I'll still watch again! Nice job & greatly appreciated...you're a natural teacher and that makes All the difference. I hope it's very gratifying for you to see how many people are positively affected by your efforts. Thanks!
Bryan Cranston used to be great, now he's just a loud mouth anti-trumper and loves telling us, the peasants outside of hollywood how to live. He's on the boycott list. Trump 2020, register to vote!
If you do not have a bench flow measuring device you can always use a shop vac and an amp clamp with a multimeter to at least find out how each port performs vs the others. Lower the amperage, lower your flow. Put the shop vac hose on the combustion side of the valve and then you can get your different lift amounts against your different amperage draws. Edit: this works best for trying to make sure you have equal CFM through each cylinder when porting and polishing. It can help prevent severe unbalance between cylinders. It is just a DIY means of comparing.
THANK YOU! As a noob, I REALLY appreciate your easy-to-follow explanation of the fundamentals. No guessing on my next cam. You helped me save money and avoid unexpected/disappointing results.
Check into David Vizard Powertec 10 videos. He has a couple on cam selection that deserve paying attention to. I understand the statement about a more efficient port being compatible with a wider LSA for a smoother idle. Every video or book has useful.bits of information. Pay attention and consider all the information. Sometimes a combining of that information will be best. For a restrictive exhaust port, finish the seat angle at 40° as this will aid low lift flow. Also consider a higher ratio set of rocker arms. This gets the valve off the seat quicker and closes quicker. This also aids low lift flow. A single pattern cam tends to make more torque, provided decent ports. These two things enable use of a single pattern cam, or a cam with less split between the intake and exhaust.
Why is this not the first video to pop up when searching about basic cam information…. Literally everything you need to know compiled Into one video. People with attention span issues who are visual learners appreciate the effort you put into this video. Everything I needed to finish building this striker for my elco
Myvintageiron between you and Pete's garage you've both have given me the confidence to learn and build my 350 engine. I would like to say thank you for sharing your knowledge I truly appreciate your help and advice . You are a blessing to this 55 year's old man . I'm forever greatful. Blessings and more Blessings to you and your Family 🤗👌
myvintageiron7512 has given me confidence to build my own 350 as well and I am 74 yrs old. I have never fooled with anything in the way of motors before!!!
I have a 1970 mercury cougar with a 351 Windsor. Some years back I port matched the intake and exhaust ports, cleaned up the bowls, and ground out the EGR bumps. Put a set of Hooker headers and dual exhaust on the old girl. At 50 mph I had a severe lean misfire. I drilled the main jets out .010" that were in the stock 2 barrel carb, advanced the timing a few degrees with the stock distributor. What a street performer! No change with the camshaft.
Couple points about 17 minutes into watching this. You might have explained that the crank overcomes 4,800 lbs cumulative, not all at once. And you definitely misspoke when you got the effect of rocker ratio backwards. Cam lobe lift is multiplied by the rocker ratio to increase lift of the valve. It works backwards from the valve toward the cam lobe. Plus, if you've got 300 lbs compression of the spring, that is obviously all the work the crank does in that regard. I'll keep watching, but those have me feeling the need to spout off...
Oh maybe for you bud but thats not everybody . I daily drove a 3/4 ton 4x4 truck that ran mid 12s in the quarter DAILY !!! That Rat also gave 16 mpg while 5700lbs was being a rocket
Mate ive been in this game for the last 30 years. Ive listened to alot of guys regurgitate what someone else has told them or what they have misinterpreted from reading text that they dont totally get or understand the concepts of head and cam design . That was by far the best lecture on valvetrain fundermentals ive ever listened to. Some topics i wasnt sure on were confirmed by you just now. Thankyou. Im subscribing to the channel right now
Different math: You did - Intake cfm * .26 * 8 * % (difference intake vs exhaust) Which is - Intake cfm * .26 * 8 * (exh cfm / intake cfm) just remove both intake cfms since they cancel out and then... You can do - Exhaust cfm * .26 * 8 Gets same answer skipping a bit of extra work. It sounds like head exhaust flow is what is the limit, not the intake. The different equation (always getting same answer) shows the obvious limitation if your calculations are correct. Liked this video, very informative!
I'm an engineer now, but I used to race and build engines with my dad. These videos are great, I appreciate you going into science behind what makes an engine work. These videos are awesome. Subbed
Friend of mine owns a machine shop he has a plaque that reads ok you want an engine that burns rubber runs 9 in quarter mile and gets 25 mpg.... ok now pick just one lol
Had a 1968 Chevelle 396 did the quarter mile in 10 seconds consecutive mild cam tuned up balanced where else 308 gearing cheater slicks nothing special cam just a good tune 75 in first gear 140 finish line just balanced in tune and the mileage was pretty good 32 miles to the gallon on the highway so is bullshit when you tell you you need a hairy cam to make your car go oh yeah it was a standard shift with a close-ratio gearbox actually built for the circuit
@@garyreed354 Out of curiosity what trans was you running. I like those 68 chevelles I owned 2 of them one was a 4 speed the other was 2 speed powerglide.
@@garyreed354 Cool deal. I have to admit im really surprised by your gas mileage. none of mine ever got more than maybe 12 mpg. I was running carburetors no FI... now im building my daughter a 1967 mustang. And will be going FI on this one. Going to use an overdrive trans but planning on a 390:1 rear gear and tires 295/50/15... back in early 90’s I worked in a performance shop with a dyno. Bigblock camaro 3 speed automatic and 388:1 gear so much fun. Lot of cars i built and sold over the years. It’s a disease lol.
I wish you were my autoshop teacher in high school. I've learned more in 49 minutes, than I learned in 2 yrs of autoshop. You're correct in the video, no one teaches you this stuff.
I was always confused by guys who hide their knowledge about engine building for street stuff. Like we aren't racing pal it doesn't matter if I know what you know I'm not going to use it against you. Thank you for explaining all this. my only questions is how do combustion chamber design effect HP. if the flow numbers are the same will the HP change with the design of the combustion chamber
I'm no expert but combustion chamber size has to do with compression. Smaller cc's will get you higher compression. Not sure how it all related to HP though.
Very good info indeed. Love the demystification of LSA Especially how it relates to OBD2 controlled engines. The head flow number analysis was certainly the icing on the cake! Thanks a million.
Honestly, after watching through it a few times and finding data and doing my math along with yours, I’m about to watch part 2 but I’m already so much closer to finding the cam I wanted then I was a few days ago. Considering I’m doing a restorative ‘super-stock’ rebuild all of the generic -shoved in your face- cams were all way bigger then I wanted. I was missing the math to find the right one, now I can actually build the set up I Wanted, instead of some cookie cutter combination.
So if I understood you correctly, I should keep my stock heads, buy the biggest baddest cam they make, hack off my mufflers, add a bunch of stickers and everyone will think my car is cool.
Engineering Explained Needs To Take Notes; This Is The Most Comprehensive Explanation I've Seen On The Net. You're Definitely One Of The Best, If Not The Best YT Channel In Regards To The Engineering Behind Engine Building. 100K Subs On The Way; Perhaps 1M In The Future? With This Level Of Detail & Analysis, The Possibilities For Growth Are Endless! *Clicks Subscribe*
@@acruzp my phone does it sometimes after I put the caps lock on for something like "HP". Then it wants to capitalize the first letter of everything for that text session. I'm sure he's not doing it on purpose.
I have a 1985 1 ton 4 speed dodge truck with a stock 360 engine. I want more power for moving heavy weight on the highway usually from 0-70 MPH. It has 2" dual exhaust and short headers. How should I build it? Which camshaft, heads, intake, and carburetor should I use?
Hands down, best video I’ve seen on camshaft and cylinder head fundamentals! The way you teach makes this so understandable, I will be reverting back to this vehicle when it comes time to build up my Monte Carlo. Thank you for taking time to make this video.
Jim myers. So true on Dyno's. In the real word, no increase in HP, but when you excelerate is where the difference is. The shorter rod, with the increased early piston speed, increases the flow low end. Thus an increase in low end torque. Very torky from stop & go!
I'm finding this GEM 3 years after you dropped it here and I appreciate you so much for it! This was great. Your video answered my original question and then some. Thank you for this!
Damn I was so spot on 20 years ago with my Chevy 350 in my k1500. New stock crate motor I put a comp cam 480/480 @280/280. It had i nice choppy idle and ran really good for a daily driver. Perfect cam for the motor at that time. Later I did much more but at that time I picked the perfect cam not knowing all of this.
I appreciate your video it was very easy to follow and very informative. I learned alot i had an idea on how to choose a cam for a engine but the part on valve lift and to aim for a cam around the peak flow numbers also the math hept alot aswell. So hey man what cam should i get for my motor lol jk. Thanks again
The magic word here is STREETABILITY. Most home built engines have too much cam and too much carburetion. Listen to this man and learn some theory. Apply this theory when building your engine and you will have a winner.
Got to have a flow bench for that because you can have the 2 sets of heads one stock one ported and they will flow differently that's why a flow bench is used to test the heads it's like the Dyno for the heads
Increasing lsa widens the rpm range and flattens peak power. Tighter lsa narrows power band and makes the powerband more peaky. Tighter lsa lessens both high and low rpm range, lessens vaccum and drivability. Wider lsa widens powerband, increases vacuum and drivability, something a dyno cant show.
@@racerd9669 correct. its all about when you close the valve. now I'm gonna combine what he said in the video with what I know about cranking compression and get something that runs right for the heads I pick and not rattle on 92 octane
@@KingJT80 Yes, but his understanding of airflow thru the engine is all wrong. No 4 stroke engine breaths at max vale lift. The intake breaths at peak flow demand, which is 2deg past peak piston speed. So the rod stroke ratio sets that point. As far as the Ex , you have to meet your 70% flow balance when the piston is at BDC on the Ex stroke , so say you have 200cfm at peak flow demand valve lift, then at BDC on the Ex stroke you will need 70% of 250cfm.
Sadly from 2030 on all combustion cars including classics will be banned from public streets in entire EU and Scandinavia :-( In Germany the Green Peoples Party gave order to shorten fuel supply from 2025 on by reducing all conventional fuel stations to only one state operated central gas station per city or county. Now they want to slow down all the gas station fuel pumps from 20 litre per minute to 2 litre per minute...From 2027 on in the EU certain car spare parts will be banned too....as exhaust systems, turbo chargers and even some engine and gearbox oils...California and New York will do the same from 2027 on.... So no investments should be done in oil burning cars any longer....They even created a new kind of crime here, called "Abgasbespaßung". :-(((
I always go back to this video because of how well everything is explained. There are a lot of people have this knowledge but not many people who can teach and explain it in such a way that the concepts are easily understood. Brilliant.
So happy to see this video, had to come to the realization myself through research that cam lift is tied to head flow. Seems obvious when stated, but nobody else clearly said as much.
@@79tazman Agreed, but what I meant as well was a 0.600 lift cam is useless on a head that stops flowing at 0.500, as an example. So you need to choose a cam whose max lift matches the optimal flow point, and whose duration is appropriate for the RPM range where you want to make power.
Hey man, love the vids. I got a question, when explaining the power required to rotate the cam and the spring pressure involved, 4800 lbs (7200 with the ratio) for all 16 springs. you cant combine all 16 springs can you? the cam is not opening all valves at the same time, there is always valves closing at any given point of rotation. The closing valves should decrease the power needed to rotate the cam? not only would the cam not be exerting energy compressing that spring/springs, but being on the downhill side of the lobe, wouldn't the spring pressure of the closing valve actually aid in rotation? I know it would be very little, but some. does that make any sense or have I had a few too many tonight?
Also the peak flow will been seen twice... opening & closing. If your peak lift is a little higher than peak flow it will not hurt power at all. It simply becomes a balancing act of lift (intensity ) vs valve train life.....
I don't think he meant at a moment in time. I think he meant the added amount of spring pressure in a specific period of time it takes all 16 valve to open and close for example if you were turning 6000 RPMs. There have been a lot of comments on this arguing and telling him he's wrong but I understood what he meant. In other words we're supposed to be smart enough to know he knows all 16 valve aren't closed at one time. I believe if my math is correct that would be every second the valves would all close and open 15 times at 6000 RPM and 1500 times in a minute
Spring pressure is nearly balanced due to the down slope side or valve close cycle balanced with valve opening. The rotational losses are just that, not at all due to spring pressures. The power sluggishness is mostly a function of gas velocity in/out of each cylinder not optimized for that huge camshaft. This is drastically impacted by the combination of heads and exhaust with that cam spec. The huge lift cam by geometry would also have a higher duration, not optimized for efficient in/out for that particular "stock" heads. The rest of your points were well presented!!
You're the man! This shows I almost nailed the camshaft for my Nova but I made one mistake. 355 with flat top pistons and stock 882 smogger heads. Picked at .434/.434 advertised duration 270 degrees. 1.5 ratio rockers. I probably should have grabbed something like a .404/.454 cam and made a few more HP. Ran a 14.7@96mph in the 1/4 mi (it was an all weather street car with 2.73 rear axle ratio) which means roughly 275-ish HP. I thought Vortec heads would have given me 300hp but your numbers say otherwise! I'm even more impressed with those 882 Camaro heads now!
On the exhaust side of the heads, stick your finger in there where the header bolts on in the roof (top) , if you grind out that bump in all the cylinders, thats worth 25 hp all by itself. And carefully grinding a little of the short turn radius on the intake port should give you another 20 hp. Dont go crazy or you will hit water.Thats free hp. that didnt cost you a dime. And you can put your intake valves in a drill press and taper the combustion chamber side outboard edges, also worth 15 hp. Theres 60hp free between those 3 tricks. If you are interested in real power gains in porting, check out Darin Morgan.
@@donrutter6765 I sold the car a few years go. I am currently looking into an old school Ford 302 build with GT40 heads and explorer intake for my Town Car. (GT40 heads are the Vortecs of the Ford world.) I'm sure there are similar tricks I can do with those heads.
@Vivian Stimpson I sold the car a few years ago. The goal was to be able to drive it anywhere at any time and it did quite well even without OD. I wanted to replace the TH350 with a 200R4 or an NV3500 and use 4:10 axle ratio. Probably would have made it a 13 sec car if I changed gears and did nothing else.
882’s were the only decent smog heads. I have boat anchor 624’s in my 79 vette. Previous owner put a cam in. Sounds good, drives meh. Saving up for a 396 sb crate motor that i’m lookin to make 500 hp with.
Fantastic job! Most fun I’ve had with my pants on in a long time - I’m gettin’ old alright. And I’m a Mopar guy! Always knew head flow was key. Learned that the hard way when I bought my first car from a dude who slapped a big old Crane Fireball into a 318 with factory heads and induction. Sounded great, but I could accelerate a sideways turd out of my constipated ass than that engine could accelerate my Charger. The key for me in this presentation was calculating HP based on % of flow between intake and exhaust - which I believe is a method of determining volumetric efficiency. The old rule of thumb (2HP per 1 CFM at max lift) is just a rough estimate. Now I see how the ability of a head to translate flow between intake and exhaust makes a massive difference in HP potential of the head. Great job! Now I can actually figure out a sane bumpstick for the 440 in my ‘70 R/T!!!
You missed a part in LSA explanation. The tighter the LSA or lower number ie 104 over 114, the more concentrated the " coming into the cam". Like a 2 stroke. This is also in part to the tighter LSA retaining the cylinder pressure instead of bleeding it off. The higher the dynamic cylinder pressure, the higher the octane that needs to be run in order to prevent the pressure and heat pre igniting the mixture. Aka detonation. Not trying to step on your toes just a gee wiz that's good to note! The video was excellent information ! Btw, do you build engines for individuals?
I have to agree with RL beards .. best explained I’ve ever heard .. an I do have a question about my cam I put in my truck more specific the cam card specs cause it’s confusing me .. once I find it I will explain it with my question
So if I understood this video correctly, I should start with buying a good set of heads. Then a cam to match the air flow? Thank you so much for sharing your knowledge 👍🏿👍🏿
Most cam companies give plenty of information without a huge lecture. It's not that difficult, to figure out. Anything sub 11 second 1/4 mile times is going to be a mongrel in town to drive, however diff gears stalls etc change a lot of this issue. Fuel type methanol E85 etc also has changed the game a lot
Welcome back! Consider writing a book on engine building , we need it and you will make more money. I went through the same thing you did when I built my hot rod.
The great Smokie Yunik had one years ago & it was called HP engine building & blue printing . I have this book & it explains even more than I am hearing here in this video such as compression ratios for certain cams as well as ramp speed for how fast the valves open & close which on some engines like the Chrysler Big blocks & small blocks they can use cams that have way faster ramp speeds which makes more power because they use a larger 906 lifter where as a SBC or Ford SB & big blocks use much smaller lifters so they can't take advantage of the faster ramp speed cams unless they like a lot of the racers are doing is to bore & bush the lifter bores to use bigger lifters to get more power but it's not cheap to have done plus having to buy custom lifters to boot . This was a secret that the Mopar guys for years new about & the GM & blue oval guys didn't until years later with the good engine builders years later figuring out how they could use bigger lifters to gain more power in those engines. The book also shows oiling systems on the Chevrolet Ford & Mopar small blocks & what's needed for racing for each engine in either drag racing or road racing . Smokie was a die hard engine builder but was a big Chevrolet guy & did stuff out of the box that actually worked through years of testing racing so look into trying to find his book or even who he was & what he did back then . Blue printing a engine goes a long way for longevity of the engine as well as one that makes more power & is smoother running as well & is always worth doing even on a street engine if you have the time to do it or buy the good aftermarket parts that are already done so you don't have to do the things to the stock parts to blue print them such as beam polishing on the rods checking to make sure all rod lengths are exactly the same or that the crank throws are all the same & it goes even further into cylinder heads where chamber volumes are all Cc'd & equalized .
That was great. Thanks for the video. Can you do some more with this - like how a cam affects cylinder pressure, compression ratios vs what kind of fuel is available, etc?
So that’s why modern muscle cars don’t have the choppy idle that I like. Lol their lobe separation is wider in order to not confuse the computer. Makes perfect sense wow
This is a very detailed video. Thanks for the time you've put into it. I never really thought about getting too much lift for a crappy set of heads. One note though, if you get a higher lift cam, I think it will still make more power than a low lift cam. It hits every lift point twice except for the peak. Mid-lift numbers are important. On my sbc, I am currently running a low duration 252/264 adv cam with .550"/.546" lift. My heads can handle the lift, but I certainly believe that cam would make more power than a stock cam with a stock set of heads with upgraded springs. It's all about area under the curve. More lift is higher flow, even if you get diminishing returns for higher lift. If you're lifting the valve to .600", you're losing flow on the nose, but everywhere else, you are seeing more flow than a .450" lift cam. I know the stock heads in your example can't support the rpms of a typical cam that has .600" lift, but with an aggressive lobe, it can make much more power than a stock cam. I understand what you're saying that it takes power to spin the cam, but every lobe that is lifting is also lowering a valve. The 7200lb number looks intimidating, but it doesn't tell the whole story. I'd be interested to see how much power it actually takes to spin a cam. Thanks again for sharing your knowledge.
I would just get the cam that fits the lift you're targeting with the least amount of duration without snapping the valve open and close too fast. I don't think it'd take a custom cam to do it. so I was looking at some brodix heads ported by fox lake for a Windsor that flow well up to .600 lift. (285int/219exh) so I think i'll be better off with the howards hydralic roller cam that has 227/233 .597/.597 than the cam with .247/247 .603/.603 why hold the valve open longer if I don't need to? then id have to raise the compression to a level that might not be cool with 92 octane. there's a ton to it.
@@KingJT80 Bigger cams bleed off cylinder pressure better than smaller cams because of the longer valve overlap. You'll need less octane for a bigger cam. High lift/low duration cams are often called RV cams. I'm ok with aggressive lobes on roller lifters. I don't mind blowing the valves open quickly, but I'd rather not slam them shut.
@@EricErnst I woild rather just have the compression I need. At some point closing the valve later to "bleed off" cylinder is gonna diminish what the cam is capable of with the heads. And to bring it back the crompression is gonna have to come up. If its too.much it might not ping and detonate at low rpm on pump gas, but if my foot gets into t may rattle like crazy. I do not want that to happen and have to bu8ld it twice so thats why I was looking at the first cam rather than the second because dynamic compression plays a factor too. If the first cam need 10.25 and the the second needs like 11 to run right, cam 1 gets the nod. I dont want to have to run cam 2 at 10.25 just to bleed off aylinder pressure. Not saying it wont work but id rather not do it
@@EricErnst tso things I dont want to have to do. I do not wany to have to lower the compression on the emgine because I got the wrong cam or not run full timing thats what I mean by diminishing returns. Again not saying it won't work by why not just build it correct with the correct cam and compression so youre not crutching it? Yes you can do stuff to the piatons and combustion chamber run cold air intake get collant temps down not lug the engine with tall gears etc
I study dental surgery, and i studied general medicine before. You sir teach better, and get information across more efficiently- than any professor/doctor/specialist i’ve ever met. Kudos.
I get the point that it is an important load on the engine, especially in the region of diminishing returns where the valve opens farther than the port can use. But 4800lbs. pressure is a fallacy, unless the valves are actuated in unison. It's spread out into however many valve actuation events happen in a rotation.
'I like this lobe separation because it fits my lifestyle'😂😂😂😂😂😂😂😂 On a serious note you've got one of the more informative, down to earth channels on the subject of engine building. Thank you for sharing your knowledge.👍👍
Really enjoyed the video. I did a presentation on camshafts in my first year of engineering, I didn’t go quite as in depth as this though. Keep up the great work!
You don't post much but when you do it's always awesome!!! I'm getting my heads flowed for sure! I've watched just about all of your Chevy videos. Myself and I'm sure PLENTY of others really appreciate it 😊👍
HI. I WANT TO KNOW WHAT'S THE BEST FLAT TAPPED PERFORMANCE CAM FOR MY STOCK SBC 350? IT'S A LATE 4 MAIN BOLT, IT'S AT 0.30 OVER ON THE CYLINDERS AND IT'S GOT THE FLAT TOP PISTONS WITH TBI CYLINDER HEADS BUT IT'S CARBURATED WITH AN HEI DISTRIBUTOR, NOTHING IT'S COMPUTERIZED. IT'S GOING IN A 1976 GMC 3/4 TON 4X4 WITH A STOCK AUTOMATIC TRANSMISSION, THANK YOU AND GOD BLESS 🙏
Considering his car is illegal it is definitely not a street car, so he won’t have too much to say! Plus his mechanical knowledge is pretty limited so I am betting it would be a one-sided conversation! Throwing parts at a vehicle, watching RUclips videos and using Google is not how Mechanics are taught to diagnose a problem! That is why James is there!
Nothing wrong with cletus he comea up with crazy shit. This guy knows exactly what parts will make what horse power with what combo so people not like cletus who can throw gobs of cash at somthing really apreciate someone like thia almost breaking it down to dollars per hp wich is a real art.
Your addressing Volumetric Efficiencies.., or whether you see the glass half full or half empty.., Inefficiencies. To take it one metaphysical level deeper; you are addressing Intercomponent Parameters, in other words how does one Engine Component's Parameter affect the behavior of an engine when it reacts to the next Engine Component's Parameters as the air fuel flows thru the ports. As you said early on there really isnt anyone out there teaching how to match a cam profile to a desired performance level relative to a specific engine block. Nobody's teaching the novice what are the correct questions to ask. Nobody's teaching how to write up a paper engine or what parameters are needed based on performance desired. I went thru that dilemma back in the 90's, before the days of the internet - had to read about 70 books to understand why the engine behaves the way it does. I quickly realised a lot of people sell books, put flashy shiny pictures in their books, but they all had one thing in common; none of them explained how to match a cam profile to a block displacement relative to a specific output desired much less match a Cylinder Head to a custom built engine. I never used the "%of flow" technique you outlined, which I liked; thx for that one. I did utilise the "CFM to HP" formula you referenced but didnt use the peak Intake CFM number, rather I would deduct .100" Intake Valve lift from peak Cam Lift and use that CFM number from my Cylinder Head Intake Flow, to plug into the "CFM to HP" formula; that always got me close to actual dyno #'s. One other tip I learned was the relationship of the Cylinder Volume measurement (including the Combustion Chamber of the Cylinder Head as in Total Cylinder Volume) to Cylinder Head Intake Port Volume relationship allows one to qualify that engine's performance intensity from a grocery getter to an all out race engine. In other words, it allows one to compare apples of one engine to oranges of another engine. Take a 190 cc cylinder head intake port and divide a 615 cc cylinder including the combustion chamber, and you get a constant. Now take that same 190 cc intake port and put it on a 900 cc cylinder and the constant is decreased. Once you've performed that process often enough one begins to see a pattern. You can then qualify a 4 cylinder's performance to a v8's or any engine regardless of mfg; after all engine performance doesnt care if its a domestic block or foreign block as both are still confined to the laws of physics and we are dealing with a cylinder and airflow velocity and a few other processes but for now lets just stick with the cam and cylinder head. So, when one is choosing a cylinder head not only does one need to know what you are teaching in your vid, but one needs to understand the Intake port volume to Total Cylinder Volume relationship to improve VE%, and never mismatch your cam to engine again. In my endevors back in the 90's, a lot of confusion was removed once I discovered and understood 1) Dynamic Compression Ratio to Static Compression Ratio relationship...mostly never discussed anywhere! 2) The Slider Crank Mechanism to Cam Duration 3) Peak HP to Peak RPM; which then falls under Pump Gas or Race Gas, and that falls under Street Engine or Race Engine. I also realised in my endevors the two most confusing components for any novice engine builder to understand were the Cylinder Head(s) and the Camshaft. One has to understand engine math - no way around it. Good Vid. Thx for taking the time. Sorry for the long post but your Vid triggered in me the fun I had years ago trying to make sence of it all. Funny, as I listened to you go thru your vid and you would pause, your eyes would shift, I found myself chuckling as I new what you were thinking.., "how do I say this wothout getting to technical" lol. Thx again for taking the time ;)
I honestly dont understand a lot of this Im restoring a 1981 el camino and want to use it for a street aspect. Its for a 5.0L 305 small block in it and almost everthing in ere just went over my head. Could oyu or somebody else explain this a little more and help me understand?
I read the dated book "How to Hot Rod Small Block Chevy's" years ago. The evolution of cams has changed but understanding intake velocity versus application is the key and has not changed. The book explains it well.
I’m only 71, but in my short life, I’ve never heard a better way to describe this than you’ve done here. You’re great.
I have to agree with RL. This was very complete and spoken in laymen plus terminology.
Now get your butt out there and build yourself an engine young fellah.
You kids these days, they just dont do anything unless someone is there to push them.
@@ThunderAppeal LOL....Lets to 3, eh?
Short life?? U lived for 71 YEARS!!!!
@@whydidijointhearmy 72 now, and have a track record of being 100% correct 100% of the time…ever since my divorce 36 years ago.
I've been watching videos on RUclips since it began. I can say, with 100% certainty, that this is the most well thought out, perfectly executed, easy to understand, vastly informative, instructional, and motivational video I've seen to date. You rock dude. Dead serious. Thank you very much!
Wow thanks
This is so rudimentary and basic.
you had me until your 4800 pounds of spring pressure, that's not how that works. you don't have constant pressure on every spring. aside from that, good video.
I feel like Google will delete this because it's such good information..lol
@@oakmot5477 That's old school youtube for ya. Too bad it's being taken over by corporations & talking heads.
Please don't give them ideas
Only if you use the word "Tranny".
@@Doing_it_right_the_first_time It's a good introduction, but as with everything you gotta look around a bit before you draw conclusions. I've learned that if you really want good information, you should just buy a book.
Haha maybe youtube should bring back the 5 star rating system they had back in the day.
@@donrutter6765 I'm surprised you can even say that, If I write that word my comment vanishes in a minute.
Best 49 minutes I’ve spent on RUclips. I’ll be watching again with a notebook handy as I prepare to build my 6.0 LS.
same
Lol I have to watch this again and take notes as well, wish I would have don’ it the first time!
As will I with my 283 SBC
Call Texas speed they know ls stuff tell them Armando sent ya
@@utahcountypicazospage5412they said they dont know an Armando
This is information that the old timers kept secret when I was a kid. I had the fundamentals of how this worked before, but these essential details are priceless. I've been building engines here and there since I was 16, so 27 years. I have come close but having known this I could have nailed it so much easier than assembling, driving, adjusting, deciding to swap or modify parts to get what I wanted out of the engine, on and on... I used to try to get help like this from my step Dad, my Uncles, etc...they would NEVER tell me about this stuff. Thank you SO much for this. I'm working on an old 350 in my square body right now and will be utilizing this info and rewatching this many times. More upsetting is knowing that people I asked KNEW this and just treated me like I was stupid because I didn't know what I didn't know. I knew I was missing something and this was it - the MATH. SUBBED - thanks again!
A cam was called a 3/4 rumpty dump cam...hahaha. then I moved to Florida. Lol, they're calling out durations and had ceramic clutch plates. Wow. Things have changes a bunch, with computers.
This some amazing information, you should make a part 2 and talk about the differences in a Turbo, Nitrous, Supercharger, N/A camshaft as far as specs
The 5th engine cycle,blowdown during overlap.
I feel richard holdener has that area with dyno runs
@@KingJT80 negative his theory is every camshaft is a turbo camshaft (Aftermarket). There is way more explanation and science that is involved. Hint this video.
@@rafatrill yes it matters more when you're trying to RACE but as far as a turbo specific cam thats more of a racers edge that a street guy wouldnt really need as much and yes richard did mention that
@@KingJT80 why do u think we watch his videos to have the edge when someone wants the smoke on and off the track. That's like saying a street guy isn't a racer or doesn't go to the track once in his life
I'm glad you couldn't find a explanatory video on camshaft selection. You did an excellent job. I even took notes. Thank you for taking the time, you helped a lot of people.
Glad it was helpful!
ha i did too
Took notes with drawings , I was using ice cube trays and a fat man , lol but it all made sense .
@@g86jn1 I like Fat Girls with one leg shorter than the other.
@@sux2bu883 cruise the amputee wards of the hospitals?
Great informative video. Just one note....not all springs are being compressed at max simultaneously. Total combined spring pressure cant be 7,200lbs as pressure varies for each position on the cam lobe. I would assume its closer to about 1,500-2,500 lbs of combined constant pressure.
Great point Frank.
Good point, lower operating pressure, with the important operative word being 'constant'.
That’s what I was thinking, and wondering if the release of spring pressure helps push the cam/crank, and relieve some of that pressure while some springs are on the beginning of the cam lobe rise and some are on the fall of the cam lobe
The pressure after the cam reaches the top would be pushing down on the opposite side of the cam. Wouldn't this cancel the power lost on the opening of the valves? Regardless, this is a great video. 👍
Great point!
This is hands down the best channel on RUclips related to engine building. I’ve learned a lot but more importantly it’s helped me do all my own work and build my motor
Hence why there's only 90k subs.... A majority of the auto enthusiast community "wish" they had what it takes but only about 10% have the capacity to actually learn and retain information to be dominant in their platforms.
Buy David Vizards book, building the SBC on a budget. I've got all the books, but his is hands down the best.
I have learned alot from this guy.
I thought I knew how to pick a cam based on intended use. I never realized about matching cylinder head flow to cam lift. After watching this I went and found the flow sheet for the cylinder heads on the 383 I'm building. I was going to install higher ratio rockers for more lift but decided that stock ratio with the springs I installed might offer a little more engine life. It turns out that the cam that I accidently stumbled upon matches my cylinder heads perfectly as he described. Thanks for another great vid. Totally made my day! Lol
383? SMC or BBM?
What cam and heads for the 383¿
Something told me to have my notebook ready...glad I listened to "something" and I'll still watch again! Nice job & greatly appreciated...you're a natural teacher and that makes All the difference.
I hope it's very gratifying for you to see how many people are positively affected by your efforts. Thanks!
DUDE THIS ROCKS THANK YOU SOO MUCH!! . Wish my dad was still alive. I am adopting you.
The walter white of V8s
JESSE !
😂😂😂
No, he is Walter,
i am Jesse...
Bryan Cranston used to be great, now he's just a loud mouth anti-trumper and loves telling us, the peasants outside of hollywood how to live. He's on the boycott list. Trump 2020, register to vote!
Why re voting Trump?
If you do not have a bench flow measuring device you can always use a shop vac and an amp clamp with a multimeter to at least find out how each port performs vs the others. Lower the amperage, lower your flow. Put the shop vac hose on the combustion side of the valve and then you can get your different lift amounts against your different amperage draws.
Edit: this works best for trying to make sure you have equal CFM through each cylinder when porting and polishing. It can help prevent severe unbalance between cylinders. It is just a DIY means of comparing.
Very cool method, going to try this tonight
THANK YOU! As a noob, I REALLY appreciate your easy-to-follow explanation of the fundamentals. No guessing on my next cam. You helped me save money and avoid unexpected/disappointing results.
Check into David Vizard Powertec 10 videos. He has a couple on cam selection that deserve paying attention to. I understand the statement about a more efficient port being compatible with a wider LSA for a smoother idle. Every video or book has useful.bits of information. Pay attention and consider all the information. Sometimes a combining of that information will be best.
For a restrictive exhaust port, finish the seat angle at 40° as this will aid low lift flow. Also consider a higher ratio set of rocker arms. This gets the valve off the seat quicker and closes quicker. This also aids low lift flow. A single pattern cam tends to make more torque, provided decent ports. These two things enable use of a single pattern cam, or a cam with less split between the intake and exhaust.
This is one of the best videos on designing an engine setup that I've ever seen. Thank you for posting this.
hes pretty swift
Glad you liked it!
Why is this not the first video to pop up when searching about basic cam information…. Literally everything you need to know compiled Into one video.
People with attention span issues who are visual learners appreciate the effort you put into this video. Everything I needed to finish building this striker for my elco
cool glad it helped
Myvintageiron between you and Pete's garage you've both have given me the confidence to learn and build my 350 engine. I would like to say thank you for sharing your knowledge I truly appreciate your help and advice .
You are a blessing to this 55 year's old man . I'm forever greatful.
Blessings and more Blessings to you and your Family 🤗👌
I love pet's garage I've seen all his videos he is very good and THX for the kind words
myvintageiron7512 has given me confidence to build my own 350 as well and I am 74 yrs old. I have never fooled with anything in the way of motors before!!!
I saw how Pete rebuilt a Studebaker. I thought it was fascinating.
I have a 1970 mercury cougar with a 351 Windsor. Some years back I port matched the intake and exhaust ports, cleaned up the bowls, and ground out the EGR bumps. Put a set of Hooker headers and dual exhaust on the old girl. At 50 mph I had a severe lean misfire. I drilled the main jets out .010" that were in the stock 2 barrel carb, advanced the timing a few degrees with the stock distributor.
What a street performer!
No change with the camshaft.
Couple points about 17 minutes into watching this. You might have explained that the crank overcomes 4,800 lbs cumulative, not all at once. And you definitely misspoke when you got the effect of rocker ratio backwards. Cam lobe lift is multiplied by the rocker ratio to increase lift of the valve. It works backwards from the valve toward the cam lobe. Plus, if you've got 300 lbs compression of the spring, that is obviously all the work the crank does in that regard. I'll keep watching, but those have me feeling the need to spout off...
Calling your street car a "street/strip" car is like going to the gym once a week and saying you have a "bar/beach" body.
Dahahah😂
AIN'T IT JUST AIN'T IT 😜 lols.....But we have the virtual world.... That is where most people live...
Oh maybe for you bud but thats not everybody . I daily drove a 3/4 ton 4x4 truck that ran mid 12s in the quarter DAILY !!! That Rat also gave 16 mpg while 5700lbs was being a rocket
@@bobgyetvai9444🙄
Mate ive been in this game for the last 30 years. Ive listened to alot of guys regurgitate what someone else has told them or what they have misinterpreted from reading text that they dont totally get or understand the concepts of head and cam design . That was by far the best lecture on valvetrain fundermentals ive ever listened to. Some topics i wasnt sure on were confirmed by you just now.
Thankyou.
Im subscribing to the channel right now
Glad you liked it
This video is great! Being a free teacher is hands down the most value you can bestow upon a community!
All the valves dont open at once. But most of your information is great.
Yeah it's more of a cumulative total of pressure.
i was just thinking the same thing lol but is on right track with analysis.
@@matthewjeschke Agreed. I am hoping to make a cam choice this century. Very good and well presented information.
If I remember right there are 4 valves closed at a given rotation angle but at times all valves are either opening or closing
@@wismar1971 I honestly, wish I had seen his video when I selected a cam for my LT1, but think I got a pretty sweet cam regardless.
All of the dislikes are from guys who buy cams for their sound and brag about lift numbers.
Roflmfao. That is so true. Seen so many that the bark is worse then the bite
Different math:
You did - Intake cfm * .26 * 8 * % (difference intake vs exhaust)
Which is - Intake cfm * .26 * 8 * (exh cfm / intake cfm) just remove both intake cfms since they cancel out and then...
You can do - Exhaust cfm * .26 * 8
Gets same answer skipping a bit of extra work. It sounds like head exhaust flow is what is the limit, not the intake. The different equation (always getting same answer) shows the obvious limitation if your calculations are correct.
Liked this video, very informative!
I'm an engineer now, but I used to race and build engines with my dad. These videos are great, I appreciate you going into science behind what makes an engine work. These videos are awesome. Subbed
Hands down best explanation of these principles I’ve heard. Not too many people understand these concepts
Have yet to see anyone delve into the science of building an engine. I learned more in 15 minutes of your vids than years on the internet.
Friend of mine owns a machine shop he has a plaque that reads ok you want an engine that burns rubber runs 9 in quarter mile and gets 25 mpg.... ok now pick just one lol
Hmm....
Thanks to Sloppy Mechanics and Chinese turbos, I have all 3.
Had a 1968 Chevelle 396 did the quarter mile in 10 seconds consecutive mild cam tuned up balanced where else 308 gearing cheater slicks nothing special cam just a good tune 75 in first gear 140 finish line just balanced in tune and the mileage was pretty good 32 miles to the gallon on the highway so is bullshit when you tell you you need a hairy cam to make your car go oh yeah it was a standard shift with a close-ratio gearbox actually built for the circuit
@@garyreed354
Out of curiosity what trans was you running. I like those 68 chevelles I owned 2 of them one was a 4 speed the other was 2 speed powerglide.
@@robbiefrentz9427 munsy special order also the suspension was special caled pf41 originally like at police package and I modified it after that
@@garyreed354
Cool deal. I have to admit im really surprised by your gas mileage. none of mine ever got more than maybe 12 mpg. I was running carburetors no FI... now im building my daughter a 1967 mustang. And will be going FI on this one. Going to use an overdrive trans but planning on a 390:1 rear gear and tires 295/50/15... back in early 90’s I worked in a performance shop with a dyno. Bigblock camaro 3 speed automatic and 388:1 gear so much fun. Lot of cars i built and sold over the years. It’s a disease lol.
I wish you were my autoshop teacher in high school. I've learned more in 49 minutes, than I learned in 2 yrs of autoshop. You're correct in the video, no one teaches you this stuff.
David vizard is only guy to put in print a good guide line for camshaft selection .
I was always confused by guys who hide their knowledge about engine building for street stuff. Like we aren't racing pal it doesn't matter if I know what you know I'm not going to use it against you. Thank you for explaining all this. my only questions is how do combustion chamber design effect HP. if the flow numbers are the same will the HP change with the design of the combustion chamber
I'm no expert but combustion chamber size has to do with compression. Smaller cc's will get you higher compression. Not sure how it all related to HP though.
Higher compression means higher power potential, but it also means higher pressure in the engine. There’s a reason Diesel engines are heavy
This was the absolute best simplified explanation I've heard. Just in time for rebuilding my 302. You've really opened my eyes. Thanks.
Very informative but still I'm not sure what I want to do with my '63 327 which I'm going to rebuild here soon which will be going in my '89 C1500
This is by far the best explanation of camshafts and related valvetrain considerations that I have ever seen. Thank you sir!
Very good info indeed. Love the demystification of LSA Especially how it relates to OBD2 controlled engines.
The head flow number analysis was certainly the icing on the cake! Thanks a million.
Honestly, after watching through it a few times and finding data and doing my math along with yours, I’m about to watch part 2 but I’m already so much closer to finding the cam I wanted then I was a few days ago. Considering I’m doing a restorative ‘super-stock’ rebuild all of the generic -shoved in your face- cams were all way bigger then I wanted. I was missing the math to find the right one, now I can actually build the set up I Wanted, instead of some cookie cutter combination.
So if I understood you correctly, I should keep my stock heads, buy the biggest baddest cam they make, hack off my mufflers, add a bunch of stickers and everyone will think my car is cool.
Thanks man! Great tutorial. 31% less ignorant according the dyno. Wife doesn’t notice a difference.
Engineering Explained Needs To Take Notes; This Is The Most Comprehensive Explanation I've Seen On The Net. You're Definitely One Of The Best, If Not The Best YT Channel In Regards To The Engineering Behind Engine Building. 100K Subs On The Way; Perhaps 1M In The Future? With This Level Of Detail & Analysis, The Possibilities For Growth Are Endless! *Clicks Subscribe*
Why Do You Place An Uppercase Letter On Every Word? Did You Go To School?
@@acruzp my phone does it sometimes after I put the caps lock on for something like "HP". Then it wants to capitalize the first letter of everything for that text session. I'm sure he's not doing it on purpose.
I have a 1985 1 ton 4 speed dodge truck with a stock 360 engine. I want more power for moving heavy weight on the highway usually from 0-70 MPH. It has 2" dual exhaust and short headers. How should I build it? Which camshaft, heads, intake, and carburetor should I use?
Hands down, best video I’ve seen on camshaft and cylinder head fundamentals! The way you teach makes this so understandable, I will be reverting back to this vehicle when it comes time to build up my Monte Carlo. Thank you for taking time to make this video.
27:05 "Long rods are the best man!"......hahaha. And that's what she said.
Bradley's Building Junk it's not rod length it's piston speed! Lol.
engine masters tested this theory and results showed almost no difference long vs short rod
Jim myers. So true on Dyno's. In the real word, no increase in HP, but when you excelerate is where the difference is. The shorter rod, with the increased early piston speed, increases the flow low end. Thus an increase in low end torque. Very torky from stop & go!
Vinnie Vintage. Boy you guy's sure don't beat around the BUSH!...LoL
It's how you use the rods or I guess the rod you got 🤣
Thank you so much 😎😎😎!!!! Literally Good advice thanks so much 🙏
I'm finding this GEM 3 years after you dropped it here and I appreciate you so much for it! This was great. Your video answered my original question and then some. Thank you for this!
Where were you years ago when I needed you! ;) Oh well, building my 427 Chevy again, this is really helpful ! Thx.
Damn I was so spot on 20 years ago with my Chevy 350 in my k1500. New stock crate motor I put a comp cam 480/480 @280/280. It had i nice choppy idle and ran really good for a daily driver. Perfect cam for the motor at that time. Later I did much more but at that time I picked the perfect cam not knowing all of this.
Absolutely AWESOME. You’re a natural teacher.
Thanks!
He is an actual instructor. He's great in person. Showed me "how to" allot about engines.
Oh man ive been waiting for someone to do this video. Thanks a million
I did this video last week my man.
@@stevie..d..pontiactransamm1215 ill be over in a to check it out.
Sweet,my man.
I appreciate your video it was very easy to follow and very informative. I learned alot i had an idea on how to choose a cam for a engine but the part on valve lift and to aim for a cam around the peak flow numbers also the math hept alot aswell. So hey man what cam should i get for my motor lol jk. Thanks again
Damn, I'm glad your back! Your channel is the fantastic.
I love it when I see a new myvintageiron video pop up. 👍 you’re a great teacher, don’t stop the videos!
The magic word here is STREETABILITY. Most home built engines have too much cam and too much carburetion. Listen to this man and learn some theory. Apply this theory when building your engine and you will have a winner.
Very good info. My problem is finding someone that will test heads and give me flow numbers. Would like to have half your knowledge.
Not greedy. Lol
Got to have a flow bench for that because you can have the 2 sets of heads one stock one ported and they will flow differently that's why a flow bench is used to test the heads it's like the Dyno for the heads
EXCELLENT, THANK YOU!!!! YOU CAN TEACH AN OLD DOG.
Thank you...I bought a 279 mutha thmper cam it it works AWSOMEly and you were right tho...now I need a converter
Increasing lsa widens the rpm range and flattens peak power. Tighter lsa narrows power band and makes the powerband more peaky. Tighter lsa lessens both high and low rpm range, lessens vaccum and drivability. Wider lsa widens powerband, increases vacuum and drivability, something a dyno cant show.
Correct. He has that backwards. Tighter lobe sep will make more power sooner than a wider lobe sep, apples to apples
That really depends on how the engine is built. A wider LSA may not buold3 enough cylinder pressure that you may need so you go more narrow
@@KingJT80 Less overlap increases cylinder pressure, But the intake closing has the most effect on cranking compression
@@racerd9669 correct. its all about when you close the valve. now I'm gonna combine what he said in the video with what I know about cranking compression and get something that runs right for the heads I pick and not rattle on 92 octane
@@KingJT80 Yes, but his understanding of airflow thru the engine is all wrong. No 4 stroke engine breaths at max vale lift. The intake breaths at peak flow demand, which is 2deg past peak piston speed. So the rod stroke ratio sets that point. As far as the Ex , you have to meet your 70% flow balance when the piston is at BDC on the Ex stroke , so say you have 200cfm at peak flow demand valve lift, then at BDC on the Ex stroke you will need 70% of 250cfm.
This makes sense. Finally, someone makes sense. I can now figure it out myself instead of having to ask someone.
Sadly from 2030 on all combustion cars including classics will be banned
from public streets in entire EU and Scandinavia :-( In Germany the
Green Peoples Party gave order to shorten fuel supply from 2025 on by
reducing all conventional fuel stations to only one state operated
central gas station per city or county. Now they want to slow down all
the gas station fuel pumps from 20 litre per minute to 2 litre per
minute...From 2027 on in the EU certain car spare parts will be banned
too....as exhaust systems, turbo chargers and even some engine and
gearbox oils...California and New York will do the same from 2027 on....
So no investments should be done in oil burning cars any longer....They
even created a new kind of crime here, called "Abgasbespaßung". :-(((
I always go back to this video because of how well everything is explained. There are a lot of people have this knowledge but not many people who can teach and explain it in such a way that the concepts are easily understood. Brilliant.
So happy to see this video, had to come to the realization myself through research that cam lift is tied to head flow.
Seems obvious when stated, but nobody else clearly said as much.
Yeah the more lift means the valve opens more allowing more air and the more air means mo power
@@79tazman Agreed, but what I meant as well was a 0.600 lift cam is useless on a head that stops flowing at 0.500, as an example.
So you need to choose a cam whose max lift matches the optimal flow point, and whose duration is appropriate for the RPM range where you want to make power.
@@perotekku thank you - finally - somebody. your cam profile should match your head flow. your carb or injection map should match them both.
Your making FOOLS out of a bunch of the 3/4 & full race Cam boys ya know !!! LOL, Grate info and well presented, thanks !!!
Hey man, love the vids. I got a question, when explaining the power required to rotate the cam and the spring pressure involved, 4800 lbs (7200 with the ratio) for all 16 springs. you cant combine all 16 springs can you? the cam is not opening all valves at the same time, there is always valves closing at any given point of rotation. The closing valves should decrease the power needed to rotate the cam? not only would the cam not be exerting energy compressing that spring/springs, but being on the downhill side of the lobe, wouldn't the spring pressure of the closing valve actually aid in rotation? I know it would be very little, but some. does that make any sense or have I had a few too many tonight?
Also the peak flow will been seen twice... opening & closing. If your peak lift is a little higher than peak flow it will not hurt power at all. It simply becomes a balancing act of lift (intensity ) vs valve train life.....
16 lobes opening and closing on 2 RPM, you figure it out. Oh, don't forget overlap and duration.
I don't think he meant at a moment in time. I think he meant the added amount of spring pressure in a specific period of time it takes all 16 valve to open and close for example if you were turning 6000 RPMs. There have been a lot of comments on this arguing and telling him he's wrong but I understood what he meant. In other words we're supposed to be smart enough to know he knows all 16 valve aren't closed at one time. I believe if my math is correct that would be every second the valves would all close and open 15 times at 6000 RPM and 1500 times in a minute
Spring pressure is nearly balanced due to the down slope side or valve close cycle balanced with valve opening. The rotational losses are just that, not at all due to spring pressures. The power sluggishness is mostly a function of gas velocity in/out of each cylinder not optimized for that huge camshaft. This is drastically impacted by the combination of heads and exhaust with that cam spec. The huge lift cam by geometry would also have a higher duration, not optimized for efficient in/out for that particular "stock" heads. The rest of your points were well presented!!
You're the man! This shows I almost nailed the camshaft for my Nova but I made one mistake. 355 with flat top pistons and stock 882 smogger heads. Picked at .434/.434 advertised duration 270 degrees. 1.5 ratio rockers. I probably should have grabbed something like a .404/.454 cam and made a few more HP. Ran a 14.7@96mph in the 1/4 mi (it was an all weather street car with 2.73 rear axle ratio) which means roughly 275-ish HP. I thought Vortec heads would have given me 300hp but your numbers say otherwise! I'm even more impressed with those 882 Camaro heads now!
On the exhaust side of the heads, stick your finger in there where the header bolts on in the roof (top) , if you grind out that bump in all the cylinders, thats worth 25 hp all by itself. And carefully grinding a little of the short turn radius on the intake port should give you another 20 hp. Dont go crazy or you will hit water.Thats free hp. that didnt cost you a dime. And you can put your intake valves in a drill press and taper the combustion chamber side outboard edges, also worth 15 hp. Theres 60hp free between those 3 tricks. If you are interested in real power gains in porting, check out Darin Morgan.
@@donrutter6765 I sold the car a few years go. I am currently looking into an old school Ford 302 build with GT40 heads and explorer intake for my Town Car. (GT40 heads are the Vortecs of the Ford world.) I'm sure there are similar tricks I can do with those heads.
@Vivian Stimpson I sold the car a few years ago. The goal was to be able to drive it anywhere at any time and it did quite well even without OD. I wanted to replace the TH350 with a 200R4 or an NV3500 and use 4:10 axle ratio. Probably would have made it a 13 sec car if I changed gears and did nothing else.
882’s were the only decent smog heads. I have boat anchor 624’s in my 79 vette. Previous owner put a cam in. Sounds good, drives meh. Saving up for a 396 sb crate motor that i’m lookin to make 500 hp with.
You do a damn nice job of explaining things ,and you said at the end of your video I hope I didn't confuse you , well you didn't.KUDOS
I have always wondered how to do this (pick a cam etc) and now I know.
Thank you very much! Great Job.
Fantastic job! Most fun I’ve had with my pants on in a long time - I’m gettin’ old alright. And I’m a Mopar guy! Always knew head flow was key. Learned that the hard way when I bought my first car from a dude who slapped a big old Crane Fireball into a 318 with factory heads and induction. Sounded great, but I could accelerate a sideways turd out of my constipated ass than that engine could accelerate my Charger. The key for me in this presentation was calculating HP based on % of flow between intake and exhaust - which I believe is a method of determining volumetric efficiency. The old rule of thumb (2HP per 1 CFM at max lift) is just a rough estimate. Now I see how the ability of a head to translate flow between intake and exhaust makes a massive difference in HP potential of the head. Great job! Now I can actually figure out a sane bumpstick for the 440 in my ‘70 R/T!!!
You missed a part in LSA explanation. The tighter the LSA or lower number ie 104 over 114, the more concentrated the " coming into the cam". Like a 2 stroke. This is also in part to the tighter LSA retaining the cylinder pressure instead of bleeding it off. The higher the dynamic cylinder pressure, the higher the octane that needs to be run in order to prevent the pressure and heat pre igniting the mixture. Aka detonation. Not trying to step on your toes just a gee wiz that's good to note! The video was excellent information ! Btw, do you build engines for individuals?
This is the only video of his that I've seen, and I'm subscribing. I'm in for a ton of information!
I jus did same thing for same thought 👍
Awesome video. Helps clarify some partial info I've gotten over the years.
I have to agree with RL beards .. best explained I’ve ever heard .. an I do have a question about my cam I put in my truck more specific the cam card specs cause it’s confusing me .. once I find it I will explain it with my question
Well done Heisenberg!!!🤣
You should put all these educational videos in a playlist.
So if I understood this video correctly, I should start with buying a good set of heads. Then a cam to match the air flow? Thank you so much for sharing your knowledge 👍🏿👍🏿
Reminds me of my apprenticeship.
When he said an engine is basically an air pump.
Finally
Someone that can explain and make some sense based on flow
Thanks
Most cam companies give plenty of information without a huge lecture.
It's not that difficult, to figure out.
Anything sub 11 second 1/4 mile times is going to be a mongrel in town to drive, however diff gears stalls etc change a lot of this issue.
Fuel type methanol E85 etc also has changed the game a lot
I love how he coughs and the train stops wromping on the horn
Definitely a "must watch" video!
This guy is good.... sorry, I don't know your name Bud otherwise I wouldn't refer to you as "guy". Thank you for your knowledge.
Welcome back! Consider writing a book on engine building , we need it and you will make more money. I went through the same thing you did when I built my hot rod.
The great Smokie Yunik had one years ago & it was called HP engine building & blue printing . I have this book & it explains even more than I am hearing here in this video such as compression ratios for certain cams as well as ramp speed for how fast the valves open & close which on some engines like the Chrysler Big blocks & small blocks they can use cams that have way faster ramp speeds which makes more power because they use a larger 906 lifter where as a SBC or Ford SB & big blocks use much smaller lifters so they can't take advantage of the faster ramp speed cams unless they like a lot of the racers are doing is to bore & bush the lifter bores to use bigger lifters to get more power but it's not cheap to have done plus having to buy custom lifters to boot . This was a secret that the Mopar guys for years new about & the GM & blue oval guys didn't until years later with the good engine builders years later figuring out how they could use bigger lifters to gain more power in those engines. The book also shows oiling systems on the Chevrolet Ford & Mopar small blocks & what's needed for racing for each engine in either drag racing or road racing . Smokie was a die hard engine builder but was a big Chevrolet guy & did stuff out of the box that actually worked through years of testing racing so look into trying to find his book or even who he was & what he did back then . Blue printing a engine goes a long way for longevity of the engine as well as one that makes more power & is smoother running as well & is always worth doing even on a street engine if you have the time to do it or buy the good aftermarket parts that are already done so you don't have to do the things to the stock parts to blue print them such as beam polishing on the rods checking to make sure all rod lengths are exactly the same or that the crank throws are all the same & it goes even further into cylinder heads where chamber volumes are all Cc'd & equalized .
That was great. Thanks for the video.
Can you do some more with this - like how a cam affects cylinder pressure, compression ratios vs what kind of fuel is available, etc?
He did a video on dynamic compression ratio, do a search for it. Great info, just as you would expect.
@@Woodman_Custom_Sawing OK thanks.
So that’s why modern muscle cars don’t have the choppy idle that I like. Lol their lobe separation is wider in order to not confuse the computer. Makes perfect sense wow
This is a very detailed video. Thanks for the time you've put into it.
I never really thought about getting too much lift for a crappy set of heads. One note though, if you get a higher lift cam, I think it will still make more power than a low lift cam. It hits every lift point twice except for the peak. Mid-lift numbers are important. On my sbc, I am currently running a low duration 252/264 adv cam with .550"/.546" lift. My heads can handle the lift, but I certainly believe that cam would make more power than a stock cam with a stock set of heads with upgraded springs. It's all about area under the curve. More lift is higher flow, even if you get diminishing returns for higher lift. If you're lifting the valve to .600", you're losing flow on the nose, but everywhere else, you are seeing more flow than a .450" lift cam. I know the stock heads in your example can't support the rpms of a typical cam that has .600" lift, but with an aggressive lobe, it can make much more power than a stock cam.
I understand what you're saying that it takes power to spin the cam, but every lobe that is lifting is also lowering a valve. The 7200lb number looks intimidating, but it doesn't tell the whole story. I'd be interested to see how much power it actually takes to spin a cam.
Thanks again for sharing your knowledge.
I would just get the cam that fits the lift you're targeting with the least amount of duration without snapping the valve open and close too fast. I don't think it'd take a custom cam to do it.
so I was looking at some brodix heads ported by fox lake for a Windsor that flow well up to .600 lift. (285int/219exh)
so I think i'll be better off with the howards hydralic roller cam that has 227/233 .597/.597 than the cam with .247/247 .603/.603
why hold the valve open longer if I don't need to? then id have to raise the compression to a level that might not be cool with 92 octane. there's a ton to it.
@@KingJT80 Bigger cams bleed off cylinder pressure better than smaller cams because of the longer valve overlap. You'll need less octane for a bigger cam.
High lift/low duration cams are often called RV cams. I'm ok with aggressive lobes on roller lifters. I don't mind blowing the valves open quickly, but I'd rather not slam them shut.
@@EricErnst I woild rather just have the compression I need. At some point closing the valve later to "bleed off" cylinder is gonna diminish what the cam is capable of with the heads. And to bring it back the crompression is gonna have to come up. If its too.much it might not ping and detonate at low rpm on pump gas, but if my foot gets into t may rattle like crazy.
I do not want that to happen and have to bu8ld it twice so thats why I was looking at the first cam rather than the second because dynamic compression plays a factor too.
If the first cam need 10.25 and the the second needs like 11 to run right, cam 1 gets the nod. I dont want to have to run cam 2 at 10.25 just to bleed off aylinder pressure.
Not saying it wont work but id rather not do it
@@KingJT80 Detonation is defendant on a lot more than cam selection. Either run more octane or pull timing.
@@EricErnst tso things I dont want to have to do. I do not wany to have to lower the compression on the emgine because I got the wrong cam or not run full timing thats what I mean by diminishing returns.
Again not saying it won't work by why not just build it correct with the correct cam and compression so youre not crutching it? Yes you can do stuff to the piatons and combustion chamber run cold air intake get collant temps down not lug the engine with tall gears etc
You should seriously think about making an app for these types of calculations, great video!
The "app" would be any spreadsheet program,...Excel would be my choice. Very simple to set up.
He will make millions
It happens such App already exists, look for "Engine Builder" in the App Store.
So how does the average guy get head flow numbers given they don't have access or proximity to a flow bench
Genius, teaching is a work of art, and simplification is perfection.
I study dental surgery, and i studied general medicine before. You sir teach better, and get information across more efficiently- than any professor/doctor/specialist i’ve ever met. Kudos.
I get the point that it is an important load on the engine, especially in the region of diminishing returns where the valve opens farther than the port can use. But 4800lbs. pressure is a fallacy, unless the valves are actuated in unison. It's spread out into however many valve actuation events happen in a rotation.
I feel like I just got a 7 year University Degree in Engine Perfection 101
Think I'll turn my 882's into boat anchors now...
'I like this lobe separation because it fits my lifestyle'😂😂😂😂😂😂😂😂
On a serious note you've got one of the more informative, down to earth channels on the subject of engine building. Thank you for sharing your knowledge.👍👍
😁
Can u talk about a cam for a c4 93 corvette that is stock. Base model.
Really enjoyed the video. I did a presentation on camshafts in my first year of engineering, I didn’t go quite as in depth as this though. Keep up the great work!
You don't post much but when you do it's always awesome!!! I'm getting my heads flowed for sure! I've watched just about all of your Chevy videos. Myself and I'm sure PLENTY of others really appreciate it 😊👍
THX
HI. I WANT TO KNOW WHAT'S THE BEST FLAT TAPPED PERFORMANCE CAM FOR MY STOCK SBC 350? IT'S A LATE 4 MAIN BOLT, IT'S AT 0.30 OVER ON THE CYLINDERS AND IT'S GOT THE FLAT TOP PISTONS WITH TBI CYLINDER HEADS BUT IT'S CARBURATED WITH AN HEI DISTRIBUTOR, NOTHING IT'S COMPUTERIZED. IT'S GOING IN A 1976 GMC 3/4 TON 4X4 WITH A STOCK AUTOMATIC TRANSMISSION, THANK YOU AND GOD BLESS 🙏
Engine pro MC1730
"it's either a street car or a strip car"
Cleetus McFarland would like a word with you.
Considering his car is illegal it is definitely not a street car, so he won’t have too much to say! Plus his mechanical knowledge is pretty limited so I am betting it would be a one-sided conversation! Throwing parts at a vehicle, watching RUclips videos and using Google is not how Mechanics are taught to diagnose a problem! That is why James is there!
Nothing wrong with cletus he comea up with crazy shit. This guy knows exactly what parts will make what horse power with what combo so people not like cletus who can throw gobs of cash at somthing really apreciate someone like thia almost breaking it down to dollars per hp wich is a real art.
@@johnjenkins7060 Lol, think you let your mind run a little wild with my comment. It's not that serious.
Your addressing Volumetric Efficiencies.., or whether you see the glass half full or half empty.., Inefficiencies. To take it one metaphysical level deeper; you are addressing Intercomponent Parameters, in other words how does one Engine Component's Parameter affect the behavior of an engine when it reacts to the next Engine Component's Parameters as the air fuel flows thru the ports. As you said early on there really isnt anyone out there teaching how to match a cam profile to a desired performance level relative to a specific engine block. Nobody's teaching the novice what are the correct questions to ask. Nobody's teaching how to write up a paper engine or what parameters are needed based on performance desired. I went thru that dilemma back in the 90's, before the days of the internet - had to read about 70 books to understand why the engine behaves the way it does. I quickly realised a lot of people sell books, put flashy shiny pictures in their books, but they all had one thing in common; none of them explained how to match a cam profile to a block displacement relative to a specific output desired much less match a Cylinder Head to a custom built engine. I never used the "%of flow" technique you outlined, which I liked; thx for that one. I did utilise the "CFM to HP" formula you referenced but didnt use the peak Intake CFM number, rather I would deduct .100" Intake Valve lift from peak Cam Lift and use that CFM number from my Cylinder Head Intake Flow, to plug into the "CFM to HP" formula; that always got me close to actual dyno #'s. One other tip I learned was the relationship of the Cylinder Volume measurement (including the Combustion Chamber of the Cylinder Head as in Total Cylinder Volume) to Cylinder Head Intake Port Volume relationship allows one to qualify that engine's performance intensity from a grocery getter to an all out race engine. In other words, it allows one to compare apples of one engine to oranges of another engine. Take a 190 cc cylinder head intake port and divide a 615 cc cylinder including the combustion chamber, and you get a constant. Now take that same 190 cc intake port and put it on a 900 cc cylinder and the constant is decreased. Once you've performed that process often enough one begins to see a pattern. You can then qualify a 4 cylinder's performance to a v8's or any engine regardless of mfg; after all engine performance doesnt care if its a domestic block or foreign block as both are still confined to the laws of physics and we are dealing with a cylinder and airflow velocity and a few other processes but for now lets just stick with the cam and cylinder head. So, when one is choosing a cylinder head not only does one need to know what you are teaching in your vid, but one needs to understand the Intake port volume to Total Cylinder Volume relationship to improve VE%, and never mismatch your cam to engine again. In my endevors back in the 90's, a lot of confusion was removed once I discovered and understood
1) Dynamic Compression Ratio to Static Compression Ratio relationship...mostly never discussed anywhere!
2) The Slider Crank Mechanism to Cam Duration
3) Peak HP to Peak RPM; which then falls under Pump Gas or Race Gas, and that falls under Street Engine or Race Engine. I also realised in my endevors the two most confusing components for any novice engine builder to understand were the Cylinder Head(s) and the Camshaft. One has to understand engine math - no way around it. Good Vid. Thx for taking the time. Sorry for the long post but your Vid triggered in me the fun I had years ago trying to make sence of it all. Funny, as I listened to you go thru your vid and you would pause, your eyes would shift, I found myself chuckling as I new what you were thinking.., "how do I say this wothout getting to technical" lol. Thx again for taking the time ;)
I honestly dont understand a lot of this Im restoring a 1981 el camino and want to use it for a street aspect. Its for a 5.0L 305 small block in it and almost everthing in ere just went over my head. Could oyu or somebody else explain this a little more and help me understand?
put an engine pro MC1730 cam in that 305 and be done with it you will be happy with the result
enginepro.com/
I read the dated book "How to Hot Rod Small Block Chevy's" years ago. The evolution of cams has changed but understanding intake velocity versus application is the key and has not changed. The book explains it well.
I've got the book, but a better book is David Vizard's , How to build a SBC on a budget.