@@dannobee Hah there ya go that's something my ol hs shop teacher woulda said 30yrd ago ✌️ Loose is fast anyway, at least I thought 😁 Staying on the loose side of the spec for valve clearance is what I was told to do,a couple thou of lift lost isn't going to be noticable but your valves will probably be happier in the long run✌️
I've always run tighter second gaps and had many conversations with guys that did too, never put me wrong and never a blow up from it, BUT I'm building a serious tarmac race car ATM and think I'll pull the bottom end back down and try the larger second ring gap as the rpm is up around 8200 with this motor so it can't hurt to try a bigger second gap, thanks for the good explanation, never too old to learn a new trick 😊
@@WesternReloader I always did the same, I had a conversation with a ring manufacturer years ago that backed up the claim that tighter second gap is better, what I'll do is run it tight on this engine and in 12 months time when it comes out for a freshen up I'll go bigger second gap and try the difference
He's talking about a filled block.. I think the top takes most of the heat and agree with wide if the gap closes.. Never tried or noticed any issue with second or upper oil rail... Interesting discussion
It's the installing mechanic's job to verify the end-gap and not the machine shop's. I rebuilt this guy's engine block and ordered his parts, and he put the engine together himself. He overheated it because the ring gap was not set for a turbo application - he blamed me for not verifying the ring gap before I sold it to him. I told him that, "that's like blaming the gas station clerk for not checking the condoms for holes after you've used 'em." It's the installing mechanic's job to verify the ring gap. Olympia Engine Builders.
I feel your pain. Unfortunately, many of us American men suffer from over confidence AND control issues. Your customer hired you to do the bare minimum, and he was confident enough to do the assembly, not on a street driven 351w, but on a Turbo application. I bet he set the top ring gap at .030 inch for "maximum compression". Roflmao. When I talked to one of theses clowns after a blown engine, I would say: "no warranty on race engines....ABSOLUTELY NO WARRANTY on machine work for race short blocks that I do not assemble to my specs". Tell him he got off for a few thousand dollars for your work, and tell him that assembled race engines start at around $20k.
I have the same beliefs on the three ring gaps, but I try to take into consideration two more things; How much will the rings close up at operating temp? The top closes up much more than the second. You have to anticipate that and adjust accordingly. Also, how much does the ring open up as it seats? A C-33 AP steel ring may not wear the face at all, so it’s gap stays consistent after break in. The second ring, being a tapered face, will open up the gap .00314” per .001” of face wear. per side, which means .00628” more gap, per .001” combined face wear around the ring. That second ring can open up .020” pretty easy. So keep that in mind. This is often the reason people see a power increase “after the rings seat”. It’s not that it’s sealing more compression, it’s that the ring pack starts working better because the second may have been too tight initially. Something else to consider about blow by and gap is, on our drag outboards, some pistons only have one ring, and others have both gaps aligned on a common pin, installed from the top. They still hold 2% leakdown, no problem.
This is making me feel better..I'm building a Honda engine for a guy It's a d series... I tried to offer him a better engine but he wanted to stay factory and just build it... So, we had custom wiseco pistons made for this engine 75.5 mm bore, stroke is .163 mm longer than factory rods...when I was checking the ring gaps they were a little bigger than what was specified on the sheet from wiseco...there was three different end gaps... street ,street /strip, nitrous /boost... Well the gap is slightly larger than the nitrous boost gap setting but this engine is going from 9-1 compression all the way to 11: 00-1...The bore is exactly on par and the Pistons measure exactly on par with the correct clearance.. My machine shop guy says it'll be just fine... I think it was like 26ths... The biggest setting on the sheet was 24... I think it's about 2 to 3,000s More than the biggest measurement... This engine will never see a turbo but there's a possibility he might put a 50 shot on it at some point so I guess the slightly larger ring gap is okay....
maaaaaaaaaaaan oh MAN! This is some of THE best ring information I've ever listened to. I have always wondered if there was a gap difference between n20/turbo/alcohol/n/a, etc... Thanks tons, and have a happy 4th !
I debated myself for weeks on what to do for end gap on a 225 V-6 Dauntless Jeep Engine. Cost of boring and line honing in my area is not cheap, plus the fact many machine shops have closed down over the years, also could not get .020 rings due to several factors , they weren't available. The Cylinders measured out just over 3.75 to 3.77 throughout each. So I honed them myself and ordered standard rings and installed with 28-32 gaps....Sure that's a lot....but these little Odd-Fire engines run pretty warm too.......still waiting for the heads to get finished 4 months at another machine shop. It's become impossible to rebuild motors fast anymore.
This video clears out so many doubts, wish it had been around when I was building my motor. Would be interested to see you guys discuss piston to wall clearance.
It's amazing how if you take the oil scraper rings and bend the ends so they point back towards the piston skirt instead of having that /\ outwards, the pistons just glide in the bores instead of needing to be tugged on. And this was $0 mod was worth over 20hp on my friends car, LOVE things like that and thats what the name of the game is here!
@@alro2434 I actually tried that on the top and second ring, even though this is supposed to be an absolute NO NO and there has been no huge problems with it. It was kind of remarkable as to how low the oil consumption was as compared to the previous engines that I've done. Boosted air cooled engine, daily driven.
Thank you sir. Your expertise is ao great to hear. Ill follow this on my next build. I love that you are so humble for a man whose been 277mph at Bonneville!! God bless! you!!!
Glad this video popped up in my feed! Always good to see Lake JR on a video. Great information and tons of good concepts to think about. Gonna be taking a lot of this into consideration when I get the rest of my parts to finish my 410 windsor blower motor and have to set gaps.
I bought a set of Keith black silvalite hypereutetic pistons shortly after they came out. Probly late 90s. Installed with the gap set per instruction sheet that came with pistons. Ran great till I made my first extended WOT pass in high gear. Broke at the ring land on 4 pistons. Turns out the instructions were not correct in the very first pistons they sold. I always go on the side of caution now. A little extra gap is not terrible.
.004 per inch of bore, for a stock engine, .005 forlow boost,.006 for hugh boost. And those pistons are junk. Broke lands on 4 seperate occasions with the hyper.pistons , in one season. Put a set of forged in it, and ran for 3 seasons. No problem. The hyper. Pistons were made in Bangladesh.
I learned the strength of a forged piston from a engine I bought and he said the pistons were forged. A while later I lost all compression in #7 cylinder. When I took it apart the piston ring lands were broken and it was a cast piston. All the other pistons were forged and were fine.
As long as you lead the race or being in second 🥈 will ingest less dirt than anywhere else on the track. Bravo 👌👏 on that one Lake and Mr. Barton. Thanks again for sharing this with us Mr. Speed Jr!
Been building normally aspirated gas race engines for 20 years, and ALWAYS go a little bigger than the Total seal chart. Never had an engine butt a ring, and i leakdown the cylinders after every race, the blowby is minimal. "A little loose and she"ll still go, a little tight, and it'll be a bad night..".
I opened the hood. I checked the oil, and sprayed some belt dressing on the belt. That's as far as I got. The pistons, are underneath a bunch of stuff.
45 years ago I called TRW and asked what ring gap to run for their forged pistons on gas. Their answer was .004 per inch of cylinder bore. Never broke a ring, never scratched a cylinder.
@@rafaeltorres2886 First and foremost, spend the money and use a ring end gap filer. I bought a set of 302 Chevy pistons from them, .030 over with unfinished domes. I managed to run 14.5:1 compression on pump premium gas on the street by using a cam with a lot of overlap. The one thing I had to do was install an ignition kill switch (Joe Hunt magneto) so the engine could spin up to speed before it could light off or I broke the nose off of the starter every time. That car was rough on tires.
That goes for everything since the beginning ,,it's what we would call a rule of thumb ....but today if you are running NOS double the gap on the top ring ..the boys of road kill demonstrated what NOS does to destroy your engine. Without knowing too much about it you can see that NOS would make a lot of heat real quick real fast. And doing so wouldn't make that top compression ring grow very fast and when it touches both ends it rips off the top of your piston ... if you got the air fuel mix exactly right that's the only thing that will go wrong to your engine it makes that top ring grow really quick ... It was proven there during the show with that stock block LS probably out of a pickup truck and they NOS it to death. They did manage to make over 700 horsepower out of a stock 350 horsepower so before.. I think it was the front right side cylinder the ring stuck in the piston no Gap and part of the top of the Piston was gone ..so a quick fix was to double the ring end gap ... But what if you use a total Seal ring set up . And then only on the 2nd ring like they do on diesels ...0.004" per inch of bore x 4" bore = 0.016" + NOS = 0.032" could burn some oil ..but with total Seal rings obviously would burn less ...so what I'm getting at ..who has done this and will you give up the magic numbers for the optimum performancel
Whelp, looks like I'm opening the engine up again on this bike. Thanks for the details on the "why?". "1/8 (.125) of an inch, or 125/1000s" clarified it for me...more is fine for that second ring.
I have a mopar 360 I built. Only bored .020 and went back with stock cast iron jugs, not a hot rod. The rings I got are posi loc's. I tore the engine down with about 1k miles on it. The white coating on the bearings was still there and the cylinders set in perfect. In my opinion make sure the machine shop knows what your going to be doing.
I do .0050 per inch of bore in a stock to mild street car. Turbo I do .0060 per inch and turbo with nitrous or nitrous .0070 per inch of bore. He’s over .0080 per inch of bore but this depends on temps. I usually add at least .0005 more to the second ring. I get NOTHING in my catch cans and usually that comes down to did you clean the cylinder walls properly and get all of the stone from honing out. Jet wash will NOT clean stone out. Use transmission fluid and shop towels on the walls till you see no black coming off of the rag.
Spartan Aviation in their aircraft and power-plant mechanics course built a Lycoming engine properly then disassembled the engine and rebuilt it several times increasing the ring gap each time. They measured the hp each time with lower and lower compression and found little difference other than oil consumption and blow by. I was certainly surprised by this test. It is easy on an air cooled aircraft engine to access the pistons without removing the rod bearings. The cylinders come away from the pistons. So they were curious and did it. On an engine stand of course.
Very good information I was told 5 thousands for every inch of bore on a n/a combo is safe . I'd love to build a turbo engine but I don't know anything at all about them.
i saw a test at GM tech center on a 700 HP NASCAR cup engine where they opened the ring end gap to .125 and the engine lost less than 5 HP. lots of blowby but little HP loss
Yes. Keith black put out an article about 30 years ago where they increased gap all the way to ,060 before it changed hp and blowby. I can’t find the old article but I remember it so well. They also ran huge second gaps and made more power.
I've watched some of your videos and you use this great pistons, never revealing what kind or who makes them. What kind are they?? Went to total seal web site, no pistons!
I build single cylinder air cooled race engines some have an cast iron blocks some are iron sleeved aluminum blocks and I have found that there is major power increase for the proper end gap for the top two rings. the second ring is not a compression ring, it is an oil control ring only. If the top ring doesn't seal none of the other rings are going to do that job, oil control is their job. The pressure differential between the combustion chamber and crank case is what seals the top ring to the cylinder and crankcase. If the second ring sealed combustion pressure the top ring would not function at all.
Thanks for letting us Follow up with the new way To talk about car's and Share the knowledge 😊😊. Im a French Canadian * Québec * engine lover Building little things to enjoy life 🎉
Great information I had to watch a couple times ,built many engines and always went by the charts looks like it's time to widen the Gap, Thanks for sharing!
Hey guys good video , I bought a old Matchless G80 500 , there's a short video on my channel , anyway it was semi restored but didn't make to the road , I got it running ok, but big oil leaks , so removed the head and was astounded to see piston ½ down the bore at TDC ? Wrong piston , and I found all 3 cast rings with .125" ring gap, it ran ok and pulled ok , calculated comp 4.1:1 . Cheers .
Maybe wrong rod. When I was flipping bikes as a kid a Yamaha 2-twin I was working on had a bad rod. Bought one at a Yam shop, checked the small/big end sizes and slapped it together. turning the engine over on the bench with the heads off and.....oh F, the piston attached to the new rod didn't come up as far as the other one. Bike still ran okay, so out the door it went.
@@Cobra427Veight some had a wire wound piston have you seen one? my friend had a g80cs made a long stroke pressed up Ina needle roller crank and titanium rod with a vincent piston gave 700 cm3 the cs had a centre plug that fired thru a slot between the valves supposedly to stop wetting the plug when starting the motor it went very well but got a bit hot in city traffic the rickman bros raced a similar motor in mx in one of there metisse frames . more recently a big bore short stroke matchy g80won a race beating manx nortons and vincent twins at the goodwood festival of speed so the humble matchy can be a helluva performer the weak bit is the timing side bearing
What about a regular street engine? The biggest thing a machine shop customer complains about is oil burning. Most ring sets, ex. Sealed power, Hastings, are engineered sets. And gaps are pre set. Usually 3.5 to .004 per inch of bore. Never had a problem. Chrome top rings are hard to break in because most people drive their "new" engines too gently. They need hard acceleration to "scrub" them in. Don't let new engines idle! Worst thing! Just drive it!
Great video! If I may ask your thoughts on this setup? Maybe I will get lucky. Will be finishing up my gapping soon. 468bbc/13.5-1static compression/ Total seal Gapless rings/ wet sump/ internal balance/ Blown alcohol/ wet block/flatbottomdragboat/ 32 gears/ 11 1/8" x 16 -2 blade prop. Interesting about the top oil ring gap trick. Thanks.
In all the instructions I have ever had that comes with the rings including Total Seal has me setting the top ring end gap wider than the second, just put a new engine together, wish I had seen this sooner, I guess things change as we learn more.
I've got your advice to open the upper oil ring to match the 2nd ring on a 3 piece oil ring. What about on a 2 piece oil ring that has only one gap. Mahle just says .015 or bigger but the second ring is .023 in this Porsche turbo engine. Thanks very much for the great videos!
A good explanation. I seen engine's with to little of end gaping suffer from cold engine seizure . Cold seizure....? End gapping being tight added with over revving of a cold engine before it has reached the optimal temperature for the cylinder bore to expand .... The end result is like he says an expensive day at the office .
In Jenkin's book (mostly talking about his old small block pro-stock engines) he talked about running a tighter end gap because he had a straighter bore (honed with torque plates). if you believe this, what do you do with newer honing machines like Rottler (sp?)
Good morning gentlemen. I have learned a lot of new things watching your videos and have put it to use on my engines with great success. Now I have a question about the piston ring to ring land clearance . I understand to tight will weld or lock piston ring to the piston but what happens if we make the clearance more. Book specs says .0005 to .0025. Would we notice anything if we set it to the higher clearance? Thank you for your time. You two are the best.
Thanks! That is a great question. Too much vertical clearance is bad. It lets the rings flutter around. For no gas ported pistons, .0015 clearance is good. For gas ported rings or pistons, .001 (or tighter) is good.
Diesel a different story . Must be perfect to spec . Or hard cold start. A little loose on gas is ok. .004 to .006 per inch diameter of bore is normal. Also gaps rotate around cylinder in time randomly eventually. Excellent channel 👍
is static gap (set on a stand) very representative of ring gap at operating temp? the top ring surely sees more heat, and the the top and second ring are almost always different martials and different coatings. These differences surely affect the amount of (growth) the ring has which changes the gap during load. I could see some scenarios where gapping the top and 2nd rings the same on a stand, would result in the the top gap being tighter during operation.
I know guys that run demolition derbys and they often open up an engine and file the rings a bunch. They're a little hard to start but they will run a derby with no coolant and use the engine for years
Rebuilt a 2 stroke mx bike engine for about the 5th time. It kept seizing the piston in the bore. This time i ran the ring gaps at factory max. So far no blow up...
All depends on combustion chamber temp which is affected by fuel used. Rich or lean mix, power added, etc. Old rule thumb was .004” gap per inch of bore on street car gasoline. Going slightly bigger doesn’t usually hurt. Remember to offset ring gap locations on your pistons upon install. Plus good ring quality or mfg for seal in cylinder along with a good cylinder finish hatch pattern to match the style or material of the rings. With a straight cylinder bore. Tapper or out of round cylinder also affects ring seal. Do a quick dinkle ball hone and new rings and bearings might be cheaper but at times won’t help ring seal once cylinder worn badly. Measure twice cut once remember lol
In the way back machine I did a chart for ring end gaps based upon what the engine was doing and what its induction of it is. It is based on the multiplier in thousands of an inch of ring thickness X cylinder bore X projected torque peak RPM. Different numbers are used for different materials of the ring and the piston materials. As he said, some of the guys that worked for me over the years ended up going to other engine shops and used this formula guide. I had a couple of them call me to tell me how messed up I was that are very well known engine people of their time. Fast forward, I had one of their engines found there way to me and I had to laugh when I took it apart about found the ring gaps exactly where I would have set them based on my chart. About a year later I was at this persons shop in North Carolina and gave him some crap about it and he laughed... Pulled out my chart from his desk and asked if I had ever seen it before.... One of my guys moved back there and had gone to work for him and he gave it to him, they have used this guide ever since. Funny of what goes around and comes around in this business.
I have an old set of total seal gapless ring set where the gapless ring was on the second ring and the ring gap recomendation is wider on the top than the bottom. I trust the latest tech but just goes to show it takes a while to work out what is best. I never used that ring set as I heard guys complaining of ring flutter and oil burning back then.
I’ve ran huge second gaps for 15 years. I ran a 540 Chevy with 28 to 30 too and 34-36 second and it made 885 on pump gas on the dyno. Makes less blow by than you would think. Diesel hot pistons run a surprising small gap even on seriously boosted apps.
@@wannabecarguy just remember. Oil and water cool the block and pistons. The pistons and block, especially the pistons and valve springs will always be hotter than the oil and water. The block heats the water not the other way around. The block and pistons and valve springs heat the oil, not the other way around.
My as well give you secrets away rather than die with them. Your Knowledge will always help someone save money from big mistakes. I always did. I drag raced so it we et the car so helping someone was no big deal. Years ago GM said up to .060 ring gap they seen no lose in power just a little more blowby. Past .060 they saw power lost.
Congratulations on the video, very good information. I have a doubt, it is always said that the oil ring must have a minimum of .015" but if we try to equate the gap of the oil top ring to the 2nd ring, this would be much further away than the minimum (.015"), so when or how much would be too much gap for the oil ring?
Man such a wealth of knowledge. I messed up and did a gapless top ring on my turbo rb25 and until it gets hot at the track it smokes a decent amount. I’m not pulling any vacuum on my catch can and it seems like that could be my main issue w using these rings. That or I never seated them properly lol. Great vid!
A guy limps into the Harley shop with a sputtering engine. Removed the spark plugs and one looked fouled. Looked into the cyl and found the front piston head completely detached from the skirt. Removed the jug and found the head of the piston needed to be driven out of the cyl. Customer claims he just had 10:5 pistons installed prior to his trip. Cyl was still alive so we went back to stock and sent him along. Customer gets a cyl replaced on his aircraft engine because of low compression. Comes in and claims the CHT is constantly hotter than the other cylinders. Check everything. I asked if the install tech had checked his ring gaps. He claimed the overhaul shop had adjusted the ring gaps. I removed the cyl and found the ring gaps were all about half of their spec. Adjusted the ring gaps to spec and the problem never returned - all temps normal. The average guy thinks a tighter gap is better but doesn't understand how much ring pressure/ friction is created by combustion pressure going behind the ring ( through the gap ) - pressing it out against the cyl wall.
The second ring's mission is to reduce the load on the top ring. Unlike what most people think, the load on the top ring is not proportional to the cylinder pressure, but proportional to the pressure difference between the cylinder pressure and pressure below the top ring. The more the second ring is loaded, the more the top ring is unloaded. Therefore, having a huge endgap on the second ring will load the top ring more.
Lol, speaking of Turbo Diesels. My highly modified engine decided it was time to spit the Transfer case out, quite literally. Only thing that kept it somewhat in place was being connected to the driveshaft.... You could see daylight through it lmao. Good excuse to mode the drivetrain to match the engine I suppose.
One must always check the ring gap when building a motor it's just one of the many things you must check . Total seal rings for me every time. End Gap is application specific . A drag race motor will have a different gap than a NASCAR motor and so on and so forth. A beautiful cross hatch in the bore always helps with sitting the rings in the bore.
Well this has me 2nd guessing our choice of a Napier gapless 2nd ring. Although I have almost no blowby out the valve covers I am seeing puffs of smoke out the pipes at full throttle, ring flutter? Sbc 440 dart. Started at 427 and grew as I learned. Daily driven sniper efi and handles road trips just fill gas and check and add oil and it will go anywhere fast.
When i buikt my internal balanced forged internals nitrous 406 817 for my c3 vette i did .032 on top and .034 on second and she runs great at 11/1 on 93 pump gas NA too. Practically No blowby. Street it daily with 4500 stall shes a Beast of a 2 bolt small block.
I'm more of a road/rallye guy. I'm always looking to build for endurance. I racked up 40.000miles on my POV. What kind of ring gaps do you run on a vehicle running 18 to 20 hrs for 7 days (gas) ?
ok, your video very informative, gotta question . . . i'm helping a friend with an MG engine, the bore is 69 1/2mm or 2.74 inches, the compression ratio is 8.5 to one, and he is running a supercharcher making 7 pounds boost . . . what do you think the gaps should be on the top two compression rings?
I’m building my own motor for the first time for a dirt modified just a 350 bored over 030 and I’m just curious what you think ring gaps should be on that?
Any suggestions on gap for A Cummins 12 valve running some high boost around 60 psi thru compound turbos, any advise would be appreciated thanks for the video
Another thing about rings is that most of the load is on the outside of the cylinder, towards the exhaust manifold and the inside of the cylinder towards the intake.not so much load on the left and right sides of the cylinder so when I stagger them I put the gaps on the sides.your cylinders will thank you!
That’s why they make plstigauge/feeler gauges, etc…. Then do a rough assemble with old head gasket, pressurize the cylinder through the spark plug hole (valves closed) and listen for the intensity of the hissing blow by… do that for a few years and your experience will tell you if you’re ok or not.
All I use is Hastings and every time I measure end gaps they're dead on,if you're running nitrous you might want a little more gap and forced induction is different rings anyway but for what I do Hastings has never given me a problem.
pulled down a engine we build probably had 3 hrs max on it 302 windsor. anyways it leaned out and killed pistons big time when removing pistons and inspecting 4 out of 8 pistons top ring and second ring gaps have aligned. i know there would be some rotation of the ring but 4 of them is very strange .everything was set to KB piston specs u get with the piston so is the something you can to do help that or is it just life of the combustion engine and have to live with the fact
![Behind the Scenes of Gapless Piston Rings And Ring Flutter [#TECHTALK]](http://i.ytimg.com/vi/OFtf7l0B3kM/mqdefault.jpg)
A little loose and nobody knows...a little tight and everybody knows...
That’s right!
@@TotalSeal Big ring gap = big catch can. Small ring gap = big trash can.
@@dannobee LOL
I've built fixtures and know CTE. Too much end gap won't hurt. People over think this subject.
@@dannobee
Hah there ya go that's something my ol hs shop teacher woulda said 30yrd ago ✌️
Loose is fast anyway, at least I thought 😁
Staying on the loose side of the spec for valve clearance is what I was told to do,a couple thou of lift lost isn't going to be noticable but your valves will probably be happier in the long run✌️
I really like Jimmy; what a personable and knowledgeable guy. He's the kind of guy I would enjoy sitting down and having a conversation with.
He’s awesome!
What about standing up?
I've always run tighter second gaps and had many conversations with guys that did too, never put me wrong and never a blow up from it, BUT I'm building a serious tarmac race car ATM and think I'll pull the bottom end back down and try the larger second ring gap as the rpm is up around 8200 with this motor so it can't hurt to try a bigger second gap, thanks for the good explanation, never too old to learn a new trick 😊
Thanks for watching!
I made mine tighter on 2nd as I was told the piston isn’t as hot down there, but by a couple thou
@@WesternReloader I always did the same, I had a conversation with a ring manufacturer years ago that backed up the claim that tighter second gap is better, what I'll do is run it tight on this engine and in 12 months time when it comes out for a freshen up I'll go bigger second gap and try the difference
Remember, your tapered face second ring opens up .00628” for every .001” the face wears, easy as Pi.
He's talking about a filled block.. I think the top takes most of the heat and agree with wide if the gap closes..
Never tried or noticed any issue with second or upper oil rail...
Interesting discussion
It's the installing mechanic's job to verify the end-gap and not the machine shop's. I rebuilt this guy's engine block and ordered his parts, and he put the engine together himself. He overheated it because the ring gap was not set for a turbo application - he blamed me for not verifying the ring gap before I sold it to him. I told him that, "that's like blaming the gas station clerk for not checking the condoms for holes after you've used 'em." It's the installing mechanic's job to verify the ring gap. Olympia Engine Builders.
It’s the responsibility of the piston installer…always!
I like that analogy - I must remember it. 😄👍
I feel your pain. Unfortunately, many of us American men suffer from over confidence AND control issues. Your customer hired you to do the bare minimum, and he was confident enough to do the assembly, not on a street driven 351w, but on a Turbo application. I bet he set the top ring gap at .030 inch for "maximum compression". Roflmao. When I talked to one of theses clowns after a blown engine, I would say: "no warranty on race engines....ABSOLUTELY NO WARRANTY on machine work for race short blocks that I do not assemble to my specs". Tell him he got off for a few thousand dollars for your work, and tell him that assembled race engines start at around $20k.
lmao. uhhhh....
Could cooler burning e85 have made a difference in that situation?
I have the same beliefs on the three ring gaps, but I try to take into consideration two more things;
How much will the rings close up at operating temp? The top closes up much more than the second. You have to anticipate that and adjust accordingly.
Also, how much does the ring open up as it seats? A C-33 AP steel ring may not wear the face at all, so it’s gap stays consistent after break in.
The second ring, being a tapered face, will open up the gap .00314” per .001” of face wear. per side, which means .00628” more gap, per .001” combined face wear around the ring.
That second ring can open up .020” pretty easy. So keep that in mind. This is often the reason people see a power increase “after the rings seat”. It’s not that it’s sealing more compression, it’s that the ring pack starts working better because the second may have been too tight initially.
Something else to consider about blow by and gap is, on our drag outboards, some pistons only have one ring, and others have both gaps aligned on a common pin, installed from the top. They still hold 2% leakdown, no problem.
Very great points!
This is making me feel better..I'm building a Honda engine for a guy It's a d series... I tried to offer him a better engine but he wanted to stay factory and just build it... So, we had custom wiseco pistons made for this engine 75.5 mm bore, stroke is .163 mm longer than factory rods...when I was checking the ring gaps they were a little bigger than what was specified on the sheet from wiseco...there was three different end gaps... street ,street /strip, nitrous /boost... Well the gap is slightly larger than the nitrous boost gap setting but this engine is going from 9-1 compression all the way to 11: 00-1...The bore is exactly on par and the Pistons measure exactly on par with the correct clearance.. My machine shop guy says it'll be just fine... I think it was like 26ths... The biggest setting on the sheet was 24... I think it's about 2 to 3,000s More than the biggest measurement... This engine will never see a turbo but there's a possibility he might put a 50 shot on it at some point so I guess the slightly larger ring gap is okay....
maaaaaaaaaaaan oh MAN! This is some of THE best ring information I've ever listened to. I have always wondered if there was a gap difference between n20/turbo/alcohol/n/a, etc... Thanks tons, and have a happy 4th !
Glad it was helpful!
I debated myself for weeks on what to do for end gap on a 225 V-6 Dauntless Jeep Engine. Cost of boring and line honing in my area is not cheap, plus the fact many machine shops have closed down over the years, also could not get .020 rings due to several factors , they weren't available. The Cylinders measured out just over 3.75 to 3.77 throughout each. So I honed them myself and ordered standard rings and installed with 28-32 gaps....Sure that's a lot....but these little Odd-Fire engines run pretty warm too.......still waiting for the heads to get finished 4 months at another machine shop. It's become impossible to rebuild motors fast anymore.
Good information.
Thanks guys.
I have been opening up my second gap for a few years now.
Thanks for sharing.
Take care, Ed.
👍👍
This video clears out so many doubts, wish it had been around when I was building my motor. Would be interested to see you guys discuss piston to wall clearance.
We are glad it was helpful!
It's amazing how if you take the oil scraper rings and bend the ends so they point back towards the piston skirt instead of having that /\ outwards, the pistons just glide in the bores instead of needing to be tugged on. And this was $0 mod was worth over 20hp on my friends car, LOVE things like that and thats what the name of the game is here!
I’ll do this next time!
Better run a good vacuum pump
I'm concerned about losing oil seal. I am thinking of trying it but I drive a lot on the street
Bend?? How'bout just radius the corner?
@@alro2434 I actually tried that on the top and second ring, even though this is supposed to be an absolute NO NO and there has been no huge problems with it. It was kind of remarkable as to how low the oil consumption was as compared to the previous engines that I've done. Boosted air cooled engine, daily driven.
Thank you for including high performance diesels in this discussion.
It makes a lot of sense
We are glad it was helpful.
I learned a lot.... it makes total sense. I'll stick to modding rc engines for now tho.
Thank you sir. Your expertise is ao great to hear. Ill follow this on my next build. I love that you are so humble for a man whose been 277mph at Bonneville!! God bless! you!!!
Jimmy is the man!
Glad this video popped up in my feed! Always good to see Lake JR on a video. Great information and tons of good concepts to think about. Gonna be taking a lot of this into consideration when I get the rest of my parts to finish my 410 windsor blower motor and have to set gaps.
Glad you enjoyed it!
I bought a set of Keith black silvalite hypereutetic pistons shortly after they came out. Probly late 90s. Installed with the gap set per instruction sheet that came with pistons. Ran great till I made my first extended WOT pass in high gear. Broke at the ring land on 4 pistons. Turns out the instructions were not correct in the very first pistons they sold. I always go on the side of caution now. A little extra gap is not terrible.
Thanks for sharing.
.004 per inch of bore, for a stock engine, .005 forlow boost,.006 for hugh boost. And those pistons are junk. Broke lands on 4 seperate occasions with the hyper.pistons , in one season. Put a set of forged in it, and ran for 3 seasons. No problem. The hyper. Pistons were made in Bangladesh.
I learnt that as well way back
I learned the strength of a forged piston from a engine I bought and he said the pistons were forged. A while later I lost all compression in #7 cylinder. When I took it apart the piston ring lands were broken and it was a cast piston. All the other pistons were forged and were fine.
Thanks for sharing!
As long as you lead the race or being in second 🥈 will ingest less dirt than anywhere else on the track. Bravo 👌👏 on that one Lake and Mr. Barton. Thanks again for sharing this with us Mr. Speed Jr!
Thanks!
Been building normally aspirated gas race engines for 20 years, and ALWAYS go a little bigger than the Total seal chart. Never had an engine butt a ring, and i leakdown the cylinders after every race, the blowby is minimal.
"A little loose and she"ll still go, a little tight, and it'll be a bad night..".
Absolutely!
I opened the hood. I checked the oil, and sprayed some belt dressing on the belt. That's as far as I got. The pistons, are underneath a bunch of stuff.
LOL, they are quite inconvenient to reach.
Just screw out the spark plugs, you can get right to them. This is a secret professional mechanics don't want you to know!
If ya don't know don't touch its OK not to know someone else does.
45 years ago I called TRW and asked what ring gap to run for their forged pistons on gas. Their answer was .004 per inch of cylinder bore. Never broke a ring, never scratched a cylinder.
I agree TRW was a fantastic forged piston I ran tight gaps on those.
@@rafaeltorres2886 First and foremost, spend the money and use a ring end gap filer.
I bought a set of 302 Chevy pistons from them, .030 over with unfinished domes. I managed to run 14.5:1 compression on pump premium gas on the street by using a cam with a lot of overlap. The one thing I had to do was install an ignition kill switch (Joe Hunt magneto) so the engine could spin up to speed before it could light off or I broke the nose off of the starter every time. That car was rough on tires.
That goes for everything since the beginning ,,it's what we would call a rule of thumb ....but today if you are running NOS double the gap on the top ring ..the boys of road kill demonstrated what NOS does to destroy your engine. Without knowing too much about it you can see that NOS would make a lot of heat real quick real fast. And doing so wouldn't make that top compression ring grow very fast and when it touches both ends it rips off the top of your piston ... if you got the air fuel mix exactly right that's the only thing that will go wrong to your engine it makes that top ring grow really quick ... It was proven there during the show with that stock block LS probably out of a pickup truck and they NOS it to death. They did manage to make over 700 horsepower out of a stock 350 horsepower so before.. I think it was the front right side cylinder the ring stuck in the piston no Gap and part of the top of the Piston was gone ..so a quick fix was to double the ring end gap ... But what if you use a total Seal ring set up . And then only on the 2nd ring like they do on diesels ...0.004" per inch of bore x 4" bore = 0.016" + NOS = 0.032" could burn some oil ..but with total Seal rings obviously would burn less ...so what I'm getting at ..who has done this and will you give up the magic numbers for the optimum performancel
Yes, same for me 55 years ago.
@@rafaeltorres2886 what was your cylinder wall to piston skirt clearances
Whelp, looks like I'm opening the engine up again on this bike. Thanks for the details on the "why?". "1/8 (.125) of an inch, or 125/1000s" clarified it for me...more is fine for that second ring.
Glad to help
I have a mopar 360 I built. Only bored .020 and went back with stock cast iron jugs, not a hot rod. The rings I got are posi loc's. I tore the engine down with about 1k miles on it. The white coating on the bearings was still there and the cylinders set in perfect. In my opinion make sure the machine shop knows what your going to be doing.
great to hear from Lake Speed Jr again !
This is very interesting. I've never heard that a 2nd ring's gap should be greater than the top ring...very interesting explanation.
Glad it was helpful!
I do .0050 per inch of bore in a stock to mild street car. Turbo I do .0060 per inch and turbo with nitrous or nitrous .0070 per inch of bore. He’s over .0080 per inch of bore but this depends on temps. I usually add at least .0005 more to the second ring.
I get NOTHING in my catch cans and usually that comes down to did you clean the cylinder walls properly and get all of the stone from honing out.
Jet wash will NOT clean stone out.
Use transmission fluid and shop towels on the walls till you see no black coming off of the rag.
Right on!
One of the best short building videos I’ve watched!
Thanks!
Spartan Aviation in their aircraft and power-plant mechanics course built a Lycoming engine properly then disassembled the engine and rebuilt it several times increasing the ring gap each time. They measured the hp each time with lower and lower compression and found little difference other than oil consumption and blow by. I was certainly surprised by this test. It is easy on an air cooled aircraft engine to access the pistons without removing the rod bearings. The cylinders come away from the pistons. So they were curious and did it. On an engine stand of course.
Thanks for sharing!
Very good information I was told 5 thousands for every inch of bore on a n/a combo is safe . I'd love to build a turbo engine but I don't know anything at all about them.
Yes, that’s a safe bet for a NA engine.
George Bryce says .04 per inch for NA and .07 per inch blown.
i saw a test at GM tech center on a 700 HP NASCAR cup engine where they opened the ring end gap to .125 and the engine lost less than 5 HP. lots of blowby but little HP loss
Yes. Keith black put out an article about 30 years ago where they increased gap all the way to ,060 before it changed hp and blowby. I can’t find the old article but I remember it so well. They also ran huge second gaps and made more power.
Thanks for all the high tech info.
High rpm eng not enough time to leak at high rpm
I've watched some of your videos and you use this great pistons, never revealing what kind or who makes them. What kind are they?? Went to total seal web site, no pistons!
I build single cylinder air cooled race engines some have an cast iron blocks some are iron sleeved aluminum blocks and I have found that there is major power increase for the proper end gap for the top two rings. the second ring is not a compression ring, it is an oil control ring only. If the top ring doesn't seal none of the other rings are going to do that job, oil control is their job. The pressure differential between the combustion chamber and crank case is what seals the top ring to the cylinder and crankcase. If the second ring sealed combustion pressure the top ring would not function at all.
Absolutely!
Now THIS makes sense ^^ That's ironclad logic bro.
Thanks for letting us
Follow up with the new way
To talk about car's and
Share the knowledge 😊😊.
Im a French Canadian
* Québec * engine lover
Building little things to enjoy life 🎉
I thought that a “little loose” was just common knowledge. Thanks for this guys.
Happy to help!
Great information I had to watch a couple times ,built many engines and always went by the charts looks like it's time to widen the Gap, Thanks for sharing!
Glad it was helpful!
Hey guys good video , I bought a old Matchless G80 500 , there's a short video on my channel , anyway it was semi restored but didn't make to the road , I got it running ok, but big oil leaks , so removed the head and was astounded to see piston ½ down the bore at TDC ? Wrong piston , and I found all 3 cast rings with .125" ring gap, it ran ok and pulled ok , calculated comp 4.1:1 . Cheers .
Maybe wrong rod. When I was flipping bikes as a kid a Yamaha 2-twin I was working on had a bad rod. Bought one at a Yam shop, checked the small/big end sizes and slapped it together. turning the engine over on the bench with the heads off and.....oh F, the piston attached to the new rod didn't come up as far as the other one. Bike still ran okay, so out the door it went.
more likley a 500 top end on a 350 crank
@eweunkettles8207 definitely G80 on the crankcase , there were different pistons for different conrods , I bought a new piston, all good .
@@Cobra427Veight
some had a wire wound piston
have you seen one?
my friend had a g80cs made a long stroke pressed up Ina needle roller crank and titanium rod with a vincent piston gave 700 cm3
the cs had a centre plug that fired thru a slot between the valves
supposedly to stop wetting the plug when starting the motor it went very well but got a bit hot in city traffic
the rickman bros raced a similar motor in mx in one of there metisse frames .
more recently a big bore short stroke matchy g80won a race beating manx nortons and vincent twins at the goodwood festival of speed
so the humble matchy can be a helluva performer the weak bit is the timing side bearing
Guy's, thank you so much! This was a huge help and it saved me time and money. God bless you both!
Glad it helped!
What about a regular street engine? The biggest thing a machine shop customer complains about is oil burning. Most ring sets, ex. Sealed power, Hastings, are engineered sets. And gaps are pre set. Usually 3.5 to .004 per inch of bore. Never had a problem. Chrome top rings are hard to break in because most people drive their "new" engines too gently. They need hard acceleration to "scrub" them in. Don't let new engines idle! Worst thing! Just drive it!
Great video! If I may ask your thoughts on this setup? Maybe I will get lucky. Will be finishing up my gapping soon. 468bbc/13.5-1static compression/ Total seal Gapless rings/ wet sump/ internal balance/ Blown alcohol/ wet block/flatbottomdragboat/ 32 gears/ 11 1/8" x 16 -2 blade prop. Interesting about the top oil ring gap trick. Thanks.
Thanks for the watching and the comment, you don't need to do the oil ring trick with a Gapless ring package.
In all the instructions I have ever had that comes with the rings including Total Seal has me setting the top ring end gap wider than the second, just put a new engine together, wish I had seen this sooner, I guess things change as we learn more.
The instruction sheet recommendations are very safe. This is just cutting edge tech tips.
I've got your advice to open the upper oil ring to match the 2nd ring on a 3 piece oil ring. What about on a 2 piece oil ring that has only one gap. Mahle just says .015 or bigger but the second ring is .023 in this Porsche turbo engine. Thanks very much for the great videos!
Thanks for the question. For a two piece oil ring, just go with the .015 minimum gap.
I am glad i watched this. I just learned so much about the science behind rings & gaps.
Thanks!
A good explanation.
I seen engine's with to little of end gaping suffer from cold engine seizure .
Cold seizure....?
End gapping being tight added with over revving of a cold engine before it has reached the optimal temperature for the cylinder bore to expand ....
The end result is like he says an expensive day at the office .
In Jenkin's book (mostly talking about his old small block pro-stock engines) he talked about running a tighter end gap because he had a straighter bore (honed with torque plates). if you believe this, what do you do with newer honing machines like Rottler (sp?)
End gap is more about combustion temperature than honing technique.
Good morning gentlemen. I have learned a lot of new things watching your videos and have put it to use on my engines with great success. Now I have a question about the piston ring to ring land clearance . I understand to tight will weld or lock piston ring to the piston but what happens if we make the clearance more. Book specs says .0005 to .0025. Would we notice anything if we set it to the higher clearance? Thank you for your time. You two are the best.
Thanks! That is a great question. Too much vertical clearance is bad. It lets the rings flutter around. For no gas ported pistons, .0015 clearance is good. For gas ported rings or pistons, .001 (or tighter) is good.
I think its funny that we have been doing that for a long time even though ring manufactures said we should be doing the opposite.
Nothing like a honest man, I think 🤔 I will now investigate now if I can't or don't get a answer from now on.
I usually go 16 thousands and never had a problem on turbo builds.
I just put a 3" end gap in my rings, never have a problem!! Burns a little oil and gas gets into the oil, but it's fine!
Hahaha that's hilarious lol
I bet that motor is CLEAN !! 😉👍🏻
Such good information! Your view to subscription ratio is almost criminal!
Thanks!
wow if JR would just let these guys talk instead of interrupting his interviews
I thought it was not a bad back and forth. Both men are very worth listening to.
Diesel a different story .
Must be perfect to spec .
Or hard cold start.
A little loose on gas is ok.
.004 to .006 per inch diameter of bore is normal.
Also gaps rotate around cylinder in time randomly eventually.
Excellent channel 👍
Great point!
is static gap (set on a stand) very representative of ring gap at operating temp? the top ring surely sees more heat, and the the top and second ring are almost always different martials and different coatings. These differences surely affect the amount of (growth) the ring has which changes the gap during load. I could see some scenarios where gapping the top and 2nd rings the same on a stand, would result in the the top gap being tighter during operation.
As you mentioned, static gap is not what the operating gaps will be. The top ring gap will close up more than the 2nd ring due to the heat.
I know guys that run demolition derbys and they often open up an engine and file the rings a bunch. They're a little hard to start but they will run a derby with no coolant and use the engine for years
Thanks for sharing! That’s a great (yet extreme) example.
Rebuilt a 2 stroke mx bike engine for about the 5th time. It kept seizing the piston in the bore. This time i ran the ring gaps at factory max. So far no blow up...
Lake Love the work you do. Damn I wish you were around 30 years ago.
Thanks!
Hey youns! this was totally fun thanks a ton.
Glad you enjoyed it!
Interested in the science behind opening the top oil gap to match the second ring.
All depends on combustion chamber temp which is affected by fuel used. Rich or lean mix, power added, etc. Old rule thumb was .004” gap per inch of bore on street car gasoline. Going slightly bigger doesn’t usually hurt. Remember to offset ring gap locations on your pistons upon install. Plus good ring quality or mfg for seal in cylinder along with a good cylinder finish hatch pattern to match the style or material of the rings. With a straight cylinder bore. Tapper or out of round cylinder also affects ring seal. Do a quick dinkle ball hone and new rings and bearings might be cheaper but at times won’t help ring seal once cylinder worn badly. Measure twice cut once remember lol
In the way back machine I did a chart for ring end gaps based upon what the engine was doing and what its induction of it is. It is based on the multiplier in thousands of an inch of ring thickness X cylinder bore X projected torque peak RPM. Different numbers are used for different materials of the ring and the piston materials. As he said, some of the guys that worked for me over the years ended up going to other engine shops and used this formula guide. I had a couple of them call me to tell me how messed up I was that are very well known engine people of their time. Fast forward, I had one of their engines found there way to me and I had to laugh when I took it apart about found the ring gaps exactly where I would have set them based on my chart. About a year later I was at this persons shop in North Carolina and gave him some crap about it and he laughed... Pulled out my chart from his desk and asked if I had ever seen it before.... One of my guys moved back there and had gone to work for him and he gave it to him, they have used this guide ever since. Funny of what goes around and comes around in this business.
I have an old set of total seal gapless ring set where the gapless ring was on the second ring and the ring gap recomendation is wider on the top than the bottom. I trust the latest tech but just goes to show it takes a while to work out what is best. I never used that ring set as I heard guys complaining of ring flutter and oil burning back then.
I’ve ran huge second gaps for 15 years. I ran a 540 Chevy with 28 to 30 too and 34-36 second and it made 885 on pump gas on the dyno. Makes less blow by than you would think. Diesel hot pistons run a surprising small gap even on seriously boosted apps.
I don't see how a piston could get hotter than the engine oil .
@@wannabecarguy just remember. Oil and water cool the block and pistons. The pistons and block, especially the pistons and valve springs will always be hotter than the oil and water. The block heats the water not the other way around. The block and pistons and valve springs heat the oil, not the other way around.
@wannabecarguy
the piston sees thousands of degrees during the combustion event.
Piston crown is also in direct contact with combustion process to add to piston temp.
Let the man talk your interviewing there Mr SMARTY PANTS! 👖
Great discussion guys! Thanks for this!
Glad you enjoyed it!
My as well give you secrets away rather than die with them. Your Knowledge will always help someone save money from big mistakes. I always did. I drag raced so it we et the car so helping someone was no big deal. Years ago GM said up to .060 ring gap they seen no lose in power just a little more blowby. Past .060 they saw power lost.
Thanks!
stock set up i go with pi per inch of bore or .004 per inch of bore
Congratulations on the video, very good information.
I have a doubt, it is always said that the oil ring must have a minimum of .015" but if we try to equate the gap of the oil top ring to the 2nd ring, this would be much further away than the minimum (.015"), so when or how much would be too much gap for the oil ring?
Only the bottom oil rail needs to be .015 or larger (up to .025 for this set up), then add the extra gap to the top rail.
Always good info! Would you be willing to test a patented system that corrects the raw fuel oil dilution issue on GDI Engines?
Great video learned a few tricks
Thanks!
Man such a wealth of knowledge. I messed up and did a gapless top ring on my turbo rb25 and until it gets hot at the track it smokes a decent amount. I’m not pulling any vacuum on my catch can and it seems like that could be my main issue w using these rings. That or I never seated them properly lol. Great vid!
Thanks!
A guy limps into the Harley shop with a sputtering engine. Removed the spark plugs and one looked fouled. Looked into the cyl and found the front piston head completely detached from the skirt. Removed the jug and found the head of the piston needed to be driven out of the cyl. Customer claims he just had 10:5 pistons installed prior to his trip. Cyl was still alive so we went back to stock and sent him along.
Customer gets a cyl replaced on his aircraft engine because of low compression. Comes in and claims the CHT is constantly hotter than the other cylinders. Check everything. I asked if the install tech had checked his ring gaps. He claimed the overhaul shop had adjusted the ring gaps. I removed the cyl and found the ring gaps were all about half of their spec. Adjusted the ring gaps to spec and the problem never returned - all temps normal.
The average guy thinks a tighter gap is better but doesn't understand how much ring pressure/ friction is created by combustion pressure going behind the ring ( through the gap ) - pressing it out against the cyl wall.
Back off the talk, Lake..... and let Jimmy "have the floor" and respond to the questions... himself. Anyway... Great subject matter!
Noted!
Got a chuckle from hearing Jimmy say at 7:11 that nothing seals 100% (of course), while the logo on his shirt defiantly proclaims otherwise! :-)
The second ring's mission is to reduce the load on the top ring. Unlike what most people think, the load on the top ring is not proportional to the cylinder pressure, but proportional to the pressure difference between the cylinder pressure and pressure below the top ring. The more the second ring is loaded, the more the top ring is unloaded. Therefore, having a huge endgap on the second ring will load the top ring more.
Very good video. can yo explain what to do with the expander . Gap , no gap ,etc. Thanks.
Leave the expander alone. You can adjust the end gap on the oil ring rails.
Lake is such a cool guy! Cheers from New Zealand 🇳🇿
Thanks!
Lol, speaking of Turbo Diesels. My highly modified engine decided it was time to spit the Transfer case out, quite literally. Only thing that kept it somewhat in place was being connected to the driveshaft.... You could see daylight through it lmao. Good excuse to mode the drivetrain to match the engine I suppose.
One must always check the ring gap when building a motor it's just one of the many things you must check . Total seal rings for me every time. End Gap is application specific . A drag race motor will have a different gap than a NASCAR motor and so on and so forth. A beautiful cross hatch in the bore always helps with sitting the rings in the bore.
👍👍
@TotalSeal 💪✌️ Total seal. People might as well by the best , I do.
Best explanation I have ever heard.
Thanks!
This is six in a row jim again how about Charles and Albert zero gab second ring set that’s a real interesting piece
Well this has me 2nd guessing our choice of a Napier gapless 2nd ring. Although I have almost no blowby out the valve covers I am seeing puffs of smoke out the pipes at full throttle, ring flutter? Sbc 440 dart. Started at 427 and grew as I learned. Daily driven sniper efi and handles road trips just fill gas and check and add oil and it will go anywhere fast.
thanks for sharing your expertise
My pleasure!
It funny that in 70s we rebuilt a lot of motors every car we bought six brothers and we never checked the endcap and always ran beautiful
The young guy....Let the man talk
When i buikt my internal balanced forged internals nitrous 406 817 for my c3 vette i did .032 on top and .034 on second and she runs great at 11/1 on 93 pump gas NA too. Practically No blowby. Street it daily with 4500 stall shes a Beast of a 2 bolt small block.
Spin it to 7500 too! 220 Flotek cnc heads ported Victor intake.
The famous philosopher John Locke - All knowledge comes from experience...........So true!
What a great video! Kudos, kind sirs.
Glad you liked it!
@@TotalSeal I loved the vast years of experience distilled into one succinct video that was all killer and no filler!
Jimmy is a treasure.
Absolutely!
I have a chevy 5.3 i’m planning to boost. Might be overkill but i’m gapping .026 and .028. Better safe than ‘sploded.
I'm more of a road/rallye guy. I'm always looking to build for endurance. I racked up 40.000miles on my POV. What kind of ring gaps do you run on a vehicle running 18 to 20 hrs for 7 days (gas) ?
ok, your video very informative, gotta question . . . i'm helping a friend with an MG engine, the bore is 69 1/2mm or 2.74 inches, the compression ratio is 8.5 to one, and he is running a supercharcher making 7 pounds boost . . . what do you think the gaps should be on the top two compression rings?
Go with .006 per inch on the top ring and then add .008 to that for the 2nd. Follow the procedure in the video for the oil rings.
@@TotalSeal thank you much!
I’m building my own motor for the first time for a dirt modified just a 350 bored over 030 and I’m just curious what you think ring gaps should be on that?
Any suggestions on gap for A Cummins 12 valve running some high boost around 60 psi thru compound turbos, any advise would be appreciated thanks for the video
Keep this stuff coming!!!!!!!!!!!!!!
Thanks!
We work on Japanese bikes at our shop. The oil rings are very thin and very challenging to file lol
Another thing about rings is that most of the load is on the outside of the cylinder, towards the exhaust manifold and the inside of the cylinder towards the intake.not so much load on the left and right sides of the cylinder so when I stagger them I put the gaps on the sides.your cylinders will thank you!
How about a video on narrow ring sets to install in stock ring width with your spacers think A series i seen in catalog ?
We have one of the spacers: ruclips.net/video/hNMskeR0vqg/видео.html
That’s why they make plstigauge/feeler gauges, etc…. Then do a rough assemble with old head gasket, pressurize the cylinder through the spark plug hole (valves closed) and listen for the intensity of the hissing blow by… do that for a few years and your experience will tell you if you’re ok or not.
It nice to hear someone say normally aspirated
All I use is Hastings and every time I measure end gaps they're dead on,if you're running nitrous you might want a little more gap and forced induction is different rings anyway but for what I do Hastings has never given me a problem.
Thanks some nice info. Ring flutter and @ high RPM the layover hump . could say it makes sense.
Glad it helped
pulled down a engine we build probably had 3 hrs max on it 302 windsor. anyways it leaned out and killed pistons big time when removing pistons and inspecting 4 out of 8 pistons top ring and second ring gaps have aligned. i know there would be some rotation of the ring but 4 of them is very strange .everything was set to KB piston specs u get with the piston so is the something you can to do help that or is it just life of the combustion engine and have to live with the fact
Detonation can cause the gaps to line up
@@TotalSealSource or background on this?
Wow! Aligned rings caused by detonation 🤯