Another great job. Looking forward to the entire cam series. Cams have been black magic for a long time but you are making them much easier to understand. Thank you
If I could go back in time when i was 17-18 years old. I would be sitting at the door of your shop every morning until you adopted me and taught me everything you know.
I don't need a cam but if I did I would just give you info like the application meaning what I want it to do and not want it to do plus whatever else has been done to the engine and running gear. It takes a long, long time to know what works and what doesn't. So being an armchair expert is not the way to go, even though I am a qualified mechanic, but not a qualified and experienced camshaft advisor/grinder. Keep doing these videos and I am sure it will help others and dispel many ill advised myths, like from "my uncle's friend's brother has this .... spec cam and it worked a treat so I want that cam". But nothing you haven't heard before.
I definitely want to Thank You for making these videos I'm learning a lot from you thanks again hopefully I can do some business with you shortly I have a pure stock dirt car here in Gaffney SC
It's time to buy a Powell Cams T-Shirt to show my appreciation and to wear it to Bobs Big Boy on Friday nights for their car show as well as to In-N-Out burger and the Peterson Automotive Museum. Here are my notes/cheat sheet for Part Two (This video): Part 2: U.G.L. = Unground Lobe. B.C. = Base Circle Cam Cores are sized just like a finished cam. They already have LSA, IC, .050 Duration and a LL established. The Core is completely finished… the Journals are finished, the ends are ground, the bolt holes and dowel pin hole are there, the distributor gear/drive gear and the fuel pump lobe are already done. What’s not done are the Lobes which are not ground but only roughed in with a mill. Example Core: U.G.L. = .230 @ .050 L.L. = .350 L.S.A. = 110 Degrees + 4 Degrees If you wanted 255 with .375 L.L. you don’t have enough material to make the Cam out of this Core because the U.G.L. is already too small! As you reduce the B.C. you add Lift. An 8620 Core has approx .100 of hardened surface after it is ground. An Induction Hardened Core is approx double or .200. The most you can realistically move Lobe Separation is a few Degrees because you have to grind way too much material off the Cam. It’s counterintuitive but big Lift Roller Cams have small Lobes and low Lift stock Cams have large Lobes. The factor is not the size of the Lobes. The factors are: How wide is the Lobe, What the difference is between the Base Circle and the Lift. You cannot assume that if you regrind a Cam that you automatically lose Lift! Sometimes, if you have a very small B.C. you run out of room so instead of grinding the angle leading off the B.C. inwards, you grind it outwards. The bigger the Cam Journal gets, The bigger the Lobe can be. Never forget you are limited to what you can do with an existing profile!
Thanks again for this masterclass in cam grinding. You mention large journal diameters and briefly why they are beneficial, could you spend some time in a future video about the pros and cons of the larger journals, especially the 70+mm.
This helps my pea brain understand how you can make a cam bigger within the hard limits. Understanding cam specs but not cam grinding blew my mind how a regrind could get "bigger"...
I think people don't realize that when you re-grind the top of the lobe... You also are grinding the base of the cam. The more you cut from the base, the more you can add to the lobe lift.
@@PowellCams IMHO larger dia lifter spreads the side thrust but big deal is that it allows a larger wheel but as you know I like inverse flanks which also reduces side thrust (or allows more acceleration) There have been big gains in both inverse and flat flank in the initial lift area IMPORTANT (well also over the nose)
I just wonder if someone could come up with a welding process to put new material on the old or roughed in lobe. I’m sure there’d be issues with distortion, but I still wonder…
Hello Daniel. These may seem like dumb questions. But here goes. Can a hyd. flat tappet cam be reground into a solid cam or vise versa? Can either type of previously mentioned cams be reground into a roller cam? Please explain your answers. Maybe a short video tutorial would be helpful. Thanks.
Another good video. I appreciate you taking the time to do these. Thank you. I think it would be helpful if you could give some concrete examples referencing base circle for some cams. How about the following the numbers for a stock LS Cam (say 202@.050 and .496 lift) and a large LS street cam(say 230@.050 .700 lift) Cam bearing bore diameter (same for both- but useful reference to see how the numbers relate to others)) Base circle diameter Distance from tip of lobe to centerline of cam core I think I get what you are saying, but am a little hazy on those relationships (I used to do OHC stuff where base circle wasn't as constrained by bearing bore diameter). Are you saying that cams are ground so the tip of the lobe always just clears the bearings bores?
Good info. It seems reasonable that a new cam grind would have the lobes, int and exh, all ground symmetrical and the same size. How about a regrind? Do you measure for the smallest lobe size, int or exh, and then grind the rest to the same overall lobe size or are all the lobes now different sizes. I guess the easier way to ask it would be, assuming valve stem heights are all the same, is the distance between the base circle and the pushrod/rocker arm assembly the same across the cam for a regrind?
I have two Clevelands and I’m hoping to get a mild roller street grind cam for it. I understand overlap, LSA and lift/duration but I would defer to your opinion for those specifications. The problem will be cores. Are they available?
I have a question. Since you purchase cores so you can grind them how you, the customer or whatever want (within limits of the raw lobe and journal), do the suppliers offer cam cores which have a different LSA so you can tighten or widen the LSA or are you locked into one core. I am a SBC lover and know little about the LSA and I am happy using things I am familiar with because of funds plus I am not setting records on the track. I have spoken to a couple cam grinders but never think to ask. I plan on purchasing the base program DragSim5 Drag-Race Vehicle Simulation that Pro Racing Sim sells for approximately $70.00 that allow you to enter cam specs and get an answer on which is the possible optimum LSA for a particular lift, duration. It is supposed to be very close as every engine does different. It is made by. My thoughts are to try and get close before trying 3 cams to test. It should help me understand what is happening a lot better with how changes go one way or the other. I do not know if this program lets you know if certain engines the parameters entered are not physically possible but I still feel this is a good learning tool and practical for choosing a good cam off the shelf or one that is recommended by a cam grinder. I feel that Billy Godbold dropped the ball in his book due to the limited coverage of LSA which he stated in an interview that this large enough to be a book on its own.
So first, ty for the questions and ty for watching our content! #1 yes multiple different core specs are available for different engine families, #2 Billy didn't spend much time on Lsa because he understands that is only a input during manufacturing, so in deciding valve events it's irrelevant. #3 lsa is a output not a input, the engine only knows opening and closing events, it has no clue what Lsa the cam has. Hope this helps 🙏
@@PowellCamsI trust a handful of people about cam info and what works and what doesn't. David Vizard, Cattledog Garage, Golds Garage (videos) and now yours. I think it was Cattledog Garage that stated LSA sorts determines how the cylinder fills and it affects low end torque and hige rpm horsepower when it drops off (wider and narrower LSA) with compression being a part of it. I still need to get all the ducks lined up in a row but getting there. Your reply is much appreciated.
I wish I had found your channel a couple of weeks ago. I just bought a Clay Smith cam for my current project. How do your prices compare (sbc), and what's the lead time? I build a couple of engines a year, usually.
I'm enjoying your very informative videos. In the mid '60's, I was involved with cam grinding. At the time, there were many stock, drag racing, classes. As my memory serves me, that's a stretch, almost all cams were spec'd by gross duration and lift. Therefore cam grinders were grinding cams with much faster rates of lift, but still the same gross duration as stock. These were termed, cheater cams. The NHRA started using duration at .050 to eliminate the use of cheater cams in the stock classes. It was called the checking clearance at that time, because at .050 you're well onto the ramps and rate of lift is set. It's very hard to cheat. That, as I remember it, became the first widespread use of duration at .050.
GoodMorning Daniel, on a stock 2006 4.8 LS , what's the ballpark max lift and duration you could get on a stock core regrind? Thank you for your awesome content!
If you could, please move the camera closer so the whiteboard fills the view. Maybe a little different angle to eliminate the glare. The drawing doesn't really show up for those of us watching on a phone.
Ok Daniel, I have a question I ordered B1 Heads with 2.300 intake valves, if I use billet solid roller could you increase the the lobe separation to smooth out probable rough idle. Or would that be possible? The heads are for a 440 Mopar.😊
@@PowellCams yeah I thought so. I'm not sure about the block but I was told that I was in need of a.060 over bore with notches for the intakes. Perhaps I'm wasting my time with a factory block. I guess I an after market Keith Black and iron would be my choice for sure.
For somebody that failed art class and never completed high school, you are a good teacher.
We appreciate that very much 🙏
I maybe failed high school biology, but when I was there, chickens didn't have nuggets, strips or balls.
@@timothybayliss6680 lol
@timothybayliss6680
Also, milk only comes from cows. Not bulls.
Another great job. Looking forward to the entire cam series. Cams have been black magic for a long time but you are making them much easier to understand. Thank you
Glad it's helpful
If I could go back in time when i was 17-18 years old. I would be sitting at the door of your shop every morning until you adopted me and taught me everything you know.
Lol, it wouldn't take long! Lol, but I really appreciate that 🙏
I second that. A damn good communicator. Wish I had that talent.
I don't need a cam but if I did I would just give you info like the application meaning what I want it to do and not want it to do plus whatever else has been done to the engine and running gear. It takes a long, long time to know what works and what doesn't. So being an armchair expert is not the way to go, even though I am a qualified mechanic, but not a qualified and experienced camshaft advisor/grinder. Keep doing these videos and I am sure it will help others and dispel many ill advised myths, like from "my uncle's friend's brother has this .... spec cam and it worked a treat so I want that cam". But nothing you haven't heard before.
That's exactly how to do it!
Your, crude drawings were exactly what I wanted to see someone do! Doesn't take much, for me to understand. Great teaching, sir!
Thank you very much!
I definitely want to Thank You for making these videos I'm learning a lot from you thanks again hopefully I can do some business with you shortly I have a pure stock dirt car here in Gaffney SC
You are so welcome
Thanks again for sharing your wealth of knowledge!
Absolutely happy to
With each video I’m understanding more. Cams have always been smoke and mirrors to me. Thanks Daniel.
Glad to hear it
Very good video, very informative. Thanks for doing this!
Glad it was helpful!
So much learning here. Thank you for your time.
My pleasure!
It's time to buy a Powell Cams T-Shirt to show my appreciation and to wear it to Bobs Big Boy on Friday nights for their car show as well as to In-N-Out burger and the Peterson Automotive Museum.
Here are my notes/cheat sheet for Part Two (This video):
Part 2:
U.G.L. = Unground Lobe.
B.C. = Base Circle
Cam Cores are sized just like a finished cam. They already have LSA, IC, .050 Duration and a LL established. The Core is completely finished… the Journals are finished, the ends are ground, the bolt holes and dowel pin hole are there, the distributor gear/drive gear and the fuel pump lobe are already done. What’s not done are the Lobes which are not ground but only roughed in with a mill.
Example Core:
U.G.L. = .230 @ .050
L.L. = .350
L.S.A. = 110 Degrees + 4 Degrees
If you wanted 255 with .375 L.L. you don’t have enough material to make the Cam out of this Core because the U.G.L. is already too small!
As you reduce the B.C. you add Lift.
An 8620 Core has approx .100 of hardened surface after it is ground. An Induction Hardened Core is approx double or .200.
The most you can realistically move Lobe Separation is a few Degrees because you have to grind way too much material off the Cam.
It’s counterintuitive but big Lift Roller Cams have small Lobes and low Lift stock Cams have large Lobes. The factor is not the size of the Lobes. The factors are:
How wide is the Lobe,
What the difference is between the Base Circle and the Lift.
You cannot assume that if you regrind a Cam that you automatically lose Lift!
Sometimes, if you have a very small B.C. you run out of room so instead of grinding the angle leading off the B.C. inwards, you grind it outwards.
The bigger the Cam Journal gets, The bigger the Lobe can be.
Never forget you are limited to what you can do with an existing profile!
Tyvm, we appreciate you 🙏
Thanks again for this masterclass in cam grinding. You mention large journal diameters and briefly why they are beneficial, could you spend some time in a future video about the pros and cons of the larger journals, especially the 70+mm.
Will do
Good stuff Daniel.
Glad it's helping
This helps my pea brain understand how you can make a cam bigger within the hard limits. Understanding cam specs but not cam grinding blew my mind how a regrind could get "bigger"...
Yes, it's shape not size.
Had a guy when I was younger. He always told people his cam was so big that he had to have the cam holes bored out in the block.😂
Lol
Informative VIDEO cool 👍
Thanks 👍
Great job
Ty!
great info on cam grinding! thanks!
No problem!
I think people don't realize that when you re-grind the top of the lobe... You also are grinding the base of the cam. The more you cut from the base, the more you can add to the lobe lift.
Correct
"The more you cut from the base, the more you can add to the lobe lift." ... I added this to my notes.
could you discuss base circle, roller diameter on side thrust and various side thrust limits for different applications CHEERS
Yes
@@PowellCams IMHO larger dia lifter spreads the side thrust but big deal is that it allows a larger wheel but as you know I like inverse flanks which also reduces side thrust (or allows more acceleration) There have been big gains in both inverse and flat flank in the initial lift area IMPORTANT (well also over the nose)
I just wonder if someone could come up with a welding process to put new material on the old or roughed in lobe. I’m sure there’d be issues with distortion, but I still wonder…
Nascar teams would hardface weld the lobes on ft cams, it's just to expensive
I use Marine corps for all my cam cores. They never fail.
💯
Hello Daniel. These may seem like dumb questions. But here goes. Can a hyd. flat tappet cam be reground into a solid cam or vise versa? Can either type of previously mentioned cams be reground into a roller cam? Please explain your answers. Maybe a short video tutorial would be helpful. Thanks.
Those are not dumb questions, will address those
Another good video. I appreciate you taking the time to do these. Thank you.
I think it would be helpful if you could give some concrete examples referencing base circle for some cams.
How about the following the numbers for a stock LS Cam (say 202@.050 and .496 lift) and a large LS street cam(say 230@.050 .700 lift)
Cam bearing bore diameter (same for both- but useful reference to see how the numbers relate to others))
Base circle diameter
Distance from tip of lobe to centerline of cam core
I think I get what you are saying, but am a little hazy on those relationships (I used to do OHC stuff where base circle wasn't as constrained by bearing bore diameter). Are you saying that cams are ground so the tip of the lobe always just clears the bearings bores?
Will elaborate
Good info. It seems reasonable that a new cam grind would have the lobes, int and exh, all ground symmetrical and the same size. How about a regrind? Do you measure for the smallest lobe size, int or exh, and then grind the rest to the same overall lobe size or are all the lobes now different sizes. I guess the easier way to ask it would be, assuming valve stem heights are all the same, is the distance between the base circle and the pushrod/rocker arm assembly the same across the cam for a regrind?
On a new cam or a regrind, if both lobes are the same lift the base circle will be the same
I have two Clevelands and I’m hoping to get a mild roller street grind cam for it. I understand overlap, LSA and lift/duration but I would defer to your opinion for those specifications. The problem will be cores. Are they available?
We have plenty of cores on the shelf
I have a question. Since you purchase cores so you can grind them how you, the customer or whatever want (within limits of the raw lobe and journal), do the suppliers offer cam cores which have a different LSA so you can tighten or widen the LSA or are you locked into one core. I am a SBC lover and know little about the LSA and I am happy using things I am familiar with because of funds plus I am not setting records on the track. I have spoken to a couple cam grinders but never think to ask. I plan on purchasing the base program DragSim5 Drag-Race Vehicle Simulation that Pro Racing Sim sells for approximately $70.00 that allow you to enter cam specs and get an answer on which is the possible optimum LSA for a particular lift, duration. It is supposed to be very close as every engine does different. It is made by. My thoughts are to try and get close before trying 3 cams to test. It should help me understand what is happening a lot better with how changes go one way or the other. I do not know if this program lets you know if certain engines the parameters entered are not physically possible but I still feel this is a good learning tool and practical for choosing a good cam off the shelf or one that is recommended by a cam grinder. I feel that Billy Godbold dropped the ball in his book due to the limited coverage of LSA which he stated in an interview that this large enough to be a book on its own.
So first, ty for the questions and ty for watching our content!
#1 yes multiple different core specs are available for different engine families,
#2 Billy didn't spend much time on Lsa because he understands that is only a input during manufacturing, so in deciding valve events it's irrelevant.
#3 lsa is a output not a input, the engine only knows opening and closing events, it has no clue what Lsa the cam has.
Hope this helps 🙏
@@PowellCamsI trust a handful of people about cam info and what works and what doesn't. David Vizard, Cattledog Garage, Golds Garage (videos) and now yours. I think it was Cattledog Garage that stated LSA sorts determines how the cylinder fills and it affects low end torque and hige rpm horsepower when it drops off (wider and narrower LSA) with compression being a part of it. I still need to get all the ducks lined up in a row but getting there. Your reply is much appreciated.
+ or - 8 to 10 degrees and 1.5* maximum lobe sep change on regrinds, so pretty much all cam companies have told me
I wish I had found your channel a couple of weeks ago. I just bought a Clay Smith cam for my current project. How do your prices compare (sbc), and what's the lead time? I build a couple of engines a year, usually.
2-3 week's
This is getting good, I'm still a little unclear where this .006 and .050 comes into play and why I need to know that.
Will clarify
I'm enjoying your very informative videos. In the mid '60's, I was involved with cam grinding. At the time, there were many stock, drag racing, classes. As my memory serves me, that's a stretch, almost all cams were spec'd by gross duration and lift. Therefore cam grinders were grinding cams with much faster rates of lift, but still the same gross duration as stock. These were termed, cheater cams. The NHRA started using duration at .050 to eliminate the use of cheater cams in the stock classes. It was called the checking clearance at that time, because at .050 you're well onto the ramps and rate of lift is set. It's very hard to cheat. That, as I remember it, became the first widespread use of duration at .050.
@@curtgiovanine141 interesting
I mistyped. I meant to say, at .050, you're well past the ramp and onto the flank.
Is there a heat treat depth that you would say is a minimum. Knowing that we can't see it. Just curious. Thanks as always
Probably. 08-.100
Interesting Stuff...a lil off base ..but what do you recommend for Flat Tappet engines for Break In Oil? Zinc Additive? Thanks
Driven Br
GoodMorning Daniel, on a stock 2006 4.8 LS , what's the ballpark max lift and duration you could get on a stock core regrind? Thank you for your awesome content!
220ish, 550 lift
@@PowellCams Thank you Sir! 😊
Have you ever ground honda k series cams?
No, we don't do swinging follower cams at this time
Thank you for your knowledge and videos USA 🇺🇸 TRUMP
Welcome!
If you could, please move the camera closer so the whiteboard fills the view. Maybe a little different angle to eliminate the glare. The drawing doesn't really show up for those of us watching on a phone.
Noted!, sorry
@@PowellCams no apologies necessary. Thank you for giving us a lot of really great knowledge. Just wanted to give a little help in return.
I found a chalkboard does better than a white board on video
how can you tell id a cam is induction or case hardened ?,,, LS first
If it's case it will be copper coated
Cam Master Flash
Lol
When is a good time to call ?
Unfortunately I stay covered up and the wife normally relays ph questions
@@PowellCams ok thanks
Ok Daniel, I have a question I ordered B1 Heads with 2.300 intake valves, if I use billet solid roller could you increase the the lobe separation to smooth out probable rough idle. Or would that be possible? The heads are for a 440 Mopar.😊
We would need more information to understand what you need
@@PowellCams yeah I thought so. I'm not sure about the block but I was told that I was in need of a.060 over bore with notches for the intakes. Perhaps I'm wasting my time with a factory block. I guess I an after market Keith Black and iron would be my choice for sure.