Does anyone know if these are okay for ring end gaps or should I get file to fit rings to get them tighter.

#1 top ring- .024"
Sec ring- .025

#3 top - .025"
Sec - .024"

#5 top - .0265"
sec - .027"

#7 top - .024
sec - .025"

#2 top - .0235"
sec - .0235"

#4 top - .0235"
sec - .024"

#6 top - .022"
sec - .024"

#8 top - .020"
sec - .022"

Are these okay or should I try getting tighter fit rings.\

It is a performance engine but mainly street driven.

Thanks
Chris.

Does anyone know if these are okay for ring end gaps or should I get file to fit rings to get them tighter.

#1 top ring- .024"
Sec ring- .025

#3 top - .025"
Sec - .024"

#5 top - .0265"
sec - .027"

#7 top - .024
sec - .025"

#2 top - .0235"
sec - .0235"

#4 top - .0235"
sec - .024"

#6 top - .022"
sec - .024"

#8 top - .020"
sec - .022"

Are these okay or should I try getting tighter fit rings.\

It is a performance engine but mainly street driven.

Thanks
Chris.
=
Unless you are running KB's it's more than I'd accept.
If you are building a mild street 6500 deal you do not need to have the trick of the week end gaps.
On a this type engine .004-.0045/ inch top & the same on the second will work just fine.

For higher RPM stuff I open up the second ring to about .005-.0055 /inch,
So,,
4.030, .016-.018 top & .second
This is normally aspirated performance

The gaps on any "performance-oriented", N.A., and no nitrous engine should be approx .016/.018 on top ring and .010/.012 on second ring. The gaps you have will run the car fine but you'll get more cylinder leakage with "looser" gaps. One more item, those rebuilder rings, which you appear to be using don't usually have "bevels" on the top ring towards the upper-inner side of the ring, enabling the compression to make a tighter seal on that ring. Also by having "looser" second rings there is more chance of higher oil consumption, as the second ring is there for more oil control than compression control, that's the reason for the inner bevel on the downside of that ring. In simple terms, the top ring "grabs"the wall on the upstroke due to cylinder pressure and the second ring "grabs" the wall tighter on the downstroke due to crankcase pressure, wiping excess oil (that gets passed the oil rings) off the wall. This is why the "less expensive" ring sets at least need that bevel. You can check the set you're using for comparison. All engines built here either leave with "Speed-Pro" rings or on higher end engines, "Total-Seals". Speed-Pro's are our first choice, but are very limited in many of the sizes we require. We are currently using a variety of "back-cuts" and many "metrics". Thanks, Gary in N.Y.
P.S. Higher power ranges, non-N.A., nitrous, or many other variables, change the equation dramatically. We don't use any cast pistons (this includes
"Hypereutectic") unless the customer insists, and on many occasions we've passed on the entire job over that particular issue.

The pistons are speed pro hyperturectic and the rings I got are federal Mogul non file fit rings right out of the box.
Maybey I should just get the file to fit rings just to have that piece of mind and if I don't do it I might regret it later on.

I may see 7000 RPM every ounce in awhile.

How about some sort of zero gap second ring?

The gaps on any "performance-oriented", N.A., and no nitrous engine should be approx .016/.018 on top ring and .010/.012 on second ring. The gaps you have will run the car fine but you'll get more cylinder leakage with "looser" gaps. One more item, those rebuilder rings, which you appear to be using don't usually have "bevels" on the top ring towards the upper-inner side of the ring, enabling the compression to make a tighter seal on that ring. Also by having "looser" second rings there is more chance of higher oil consumption, as the second ring is there for more oil control than compression control, that's the reason for the inner bevel on the downside of that ring. In simple terms, the top ring "grabs"the wall on the upstroke due to cylinder pressure and the second ring "grabs" the wall tighter on the downstroke due to crankcase pressure, wiping excess oil (that gets passed the oil rings) off the wall. This is why the "less expensive" ring sets at least need that bevel. You can check the set you're using for comparison. All engines built here either leave with "Speed-Pro" rings or on higher end engines, "Total-Seals". Speed-Pro's are our first choice, but are very limited in many of the sizes we require. We are currently using a variety of "back-cuts" and many "metrics". Thanks, Gary in N.Y.
P.S. Higher power ranges, non-N.A., nitrous, or many other variables, change the equation dramatically. We don't use any cast pistons (this includes
"Hypereutectic") unless the customer insists, and on many occasions we've passed on the entire job over that particular issue.
-
Gary,
Have you bothered to follow what almost all the OEM's are doing?
Have you read the instructions that have been revised in the last few years regarding ring gaps?
Have you talked to or perhaps even better listened to what Fed Mog / Speed Pro, Perfect Seal, Mahle,,,, the list goes on have to say about ring gaps?
Have you been to an ATEC conference lately?
Or perhaps the seminar at PRI a couple of years ago on engine performance building hosted by Fed Mog that had some of the best of the best in engine builders from NASCAR among others?

If you have I will have to assume you feel these people don't know what they are talking about??
Without exception, as far as I recollect,, they are all using & recommending a wider gap at the second ring, especially in performance applications.

With all due respect to your expertise, I believe I will just go ahead & listen to what these folks recommend, along with most performance engine builders I have discussed this with.
===========

How about some sort of zero gap second ring?

On the question of "zero gap" seconds,,,,
Here is something I have posted before so it's easier to just copy it:)
I do not use or recommend gapless rings at all any more.
As for the Total Seal ones, every engine I have ever taken apart that had them had at least one & usually more of the gaps lined up.
Almost every performance engine builder I know advises against them.
I advise against them.
I have seen absolutely no gains except for the static leakdown numbers which don't tell you crap about what's going on under a load at RPM.
I have personally seen more crankcase pressure (blowby) at higher RPM's in the same basic engines with the 2nd gapless rings.
When you read magazine articles citing great gains with the newest widget try to remember who is paying for the article or the advertising in the magazine.
I use 004-.0045 top & ..005-.0055 second gaps on most performance engines except for KB's which I use very rarely.
Even the OEM's are going to larger 2nd ring end gaps & most major ring manufacturers are recommending a wider gap also.
Just a few of my thoughts on crapless 2nd rings :D

I have not used the top gapless rings so I can't comment except to say that at temperature you have almost no gap with standard rings,,

None of this has anything to do with the Total Seal Brand in general, just the gapless second ones
They have probably one of the largest selection of rings out there when you need something "special".

-
Gary,
Have you bothered to follow what almost all the OEM's are doing?
Have you read the instructions that have been revised in the last few years regarding ring gaps?
Have you talked to or perhaps even better listened to what Fed Mog / Speed Pro, Perfect Seal, Mahle,,,, the list goes on have to say about ring gaps?
Have you been to an ATEC conference lately?
Or perhaps the seminar at PRI a couple of years ago on engine performance building hosted by Fed Mog that had some of the best of the best in engine builders from NASCAR among others?

If you have I will have to assume you feel these people don't know what they are talking about??
Without exception, as far as I recollect,, they are all using & recommending a wider gap at the second ring, especially in performance applications.

With all due respect to your expertise, I believe I will just go ahead & listen to what these folks recommend, along with most performance engine builders I have discussed this with.
===========



On the question of "zero gap" seconds,,,,
Here is something I have posted before so it's easier to just copy it:)
I do not use or recommend gapless rings at all any more.
As for the Total Seal ones, every engine I have ever taken apart that had them had at least one & usually more of the gaps lined up.
Almost every performance engine builder I know advises against them.
I advise against them.
I have seen absolutely no gains except for the static leakdown numbers which don't tell you crap about what's going on under a load at RPM.
I have personally seen more crankcase pressure (blowby) at higher RPM's in the same basic engines with the 2nd gapless rings.
When you read magazine articles citing great gains with the newest widget try to remember who is paying for the article or the advertising in the magazine.
I use 004-.0045 top & ..005-.0055 second gaps on most performance engines except for KB's which I use very rarely.
Even the OEM's are going to larger 2nd ring end gaps & most major ring manufacturers are recommending a wider gap also.
Just a few of my thoughts on crapless 2nd rings :D

I have not used the top gapless rings so I can't comment except to say that at temperature you have almost no gap with standard rings,,

None of this has anything to do with the Total Seal Brand in general, just the gapless second ones
They have probably one of the largest selection of rings out there when you need something "special".
With all due respect, you have to "read the fine print". The only reason for loosening the second ring is to relieve the pressure on the top ring, but this pertains to hi(gher) rpm applications. The last part of my post says it all. Their are variables. Perhaps I'll stop building for awhile and learn more. This way maybe we can get our next SB (468) NA Pump-Gas special up to the 800HP instead of the 750HP (732 delivered) we saw and with 23 degree heads on top of it. I'm not here to "knock" anyone but I'll go out on a limb here and say you PROBABLY (note I said probably) haven't seen as much of what we have over here in N.Y. We manage to do somewhere in the area of 300+ engines a year and have no issues whatsoever. No flat cams, no blow-by problems, and I have some motors with decent HP numbers. I've gained a fair amount of knowledge up here already, some of which you wouldn't be concerned about. And I also can tell we deal with different clientele up in this neck of the woods. Right now I'm heavily involved with BB restos, mostly round ports, getting 500+ HP with ALL factory components, and maintaining power brakes, etc. Thanks for "listening", Gary in N.Y.
P.S. We do agree on one thing, "gapless" rings are totally useless.

With all due respect, you have to "read the fine print". The only reason for loosening the second ring is to relieve the pressure on the top ring, but this pertains to hi(gher) rpm applications. The last part of my post says it all. Their are variables. Perhaps I'll stop building for awhile and learn more. This way maybe we can get our next SB (468) NA Pump-Gas special up to the 800HP instead of the 750HP (732 delivered) we saw and with 23 degree heads on top of it. I'm not here to "knock" anyone but I'll go out on a limb here and say you PROBABLY (note I said probably) haven't seen as much of what we have over here in N.Y. We manage to do somewhere in the area of 300+ engines a year and have no issues whatsoever. No flat cams, no blow-by problems, and I have some motors with decent HP numbers. I've gained a fair amount of knowledge up here already, some of which you wouldn't be concerned about. And I also can tell we deal with different clientele up in this neck of the woods. Right now I'm heavily involved with BB restos, mostly round ports, getting 500+ HP with ALL factory components, and maintaining power brakes, etc. Thanks for "listening", Gary in N.Y.
P.S. We do agree on one thing, "gapless" rings are totally useless.
=
Ok,,,
I ain't gonna belabor the point,, at least not much,, but the first sentence you wrote was
"The gaps on any "performance-oriented", N.A., and no nitrous engine should be approx .016/.018 on top ring and .010/.012 on second ring. The gaps you have will run the car fine but you'll get more cylinder leakage with "looser" gaps"
This looks to me like a direct contradiction to the first sentence in your last post??
"you have to "read the fine print". The only reason for loosening the second ring is to relieve the pressure on the top ring, but this pertains to hi(gher) rpm applications

Which BTW, in my opinion, is only partially correct
Plus, I hate fine print,, apparently us folks out here on the other coast are not bright enough to understand it :(

Now, a couple of questions,,
If the only reason to use a wider second gap is for "higher RPM applications, why is it that the OEM's along with almost all ring manufacturers I know of are now using & or recommending a wider second gap??

Secondly,, why is your "first choice" ring manufacturer (Speed Pro) one of the first to come out with a recommendation of a wider second ring gap??

You don't suppose they have gone and done a little testing on there own that has shown improvements with the newer generation of rings could have anything to do with this do you?

Or,, perhaps you are correct that the older recommendations are still fine & they just needed to issue new recommendations to confuse us common folks that ain't quite up to speed with you fellows in New York :rolleyes:

Anyway, to the original question,
Chris,
I still feel the gaps you have are a little wide for my liking & would prefer .004-.0045/ inch for your application.
And for mild performance, while it isn't my first choice I also feel you have a very good piston, again for mild performance applications.
I do think 7000 RPM is pushing the bounds of mild in anything but a rice rocket though :)

I ordered .035" file fit rings and going to use those. I heard of quite a few people using these pistons with no problems at high RPM, but I probably am pushing the limit. If I ever have to rebuild again I will be beefing up the motor or even stroklng it. I will use forged pistons next time around.

As for now these pistons are pretty new and hope they last long enough until I save enough to build another engine.

I will try to get .016" to .018" for the top ring and I still don't know about the second ring.

Thanks for the replys, sorry if I started any kind of a war, but it is good to hear different opinions.

Thanks,
Chris.

here is a pretty good site that gives some info on the functions of the rings. in this site they mention that the second ring serves a dual purpose of oil control and compression with the first ring mainly on compression control duty. i am certainly not as knowledgeable as either mike or gosfast in regards to building internal combustion engines but having SOME knowledge of turbine engines and how labyrinth seals work i SUSPECT and reiterate i only SUSPECT that the second ring may have a great deal to do with compression control also. in any case the SRP forged pistons and rings i used in my BB says to use .0045/inch on the top ring and .005/inch on the second ring. now i dont pretend to know the dynamics of why this is best but comparing this to the gap you are getting my vote is to go with some file fit rings and be on the safe side. that really does look like a LOT of gap you have there. otherwise you could end up with a HURRICANE in your oilpan :)

http://www.jepistons.com/pdf/2005-proseal.pdf

The test results I seen related to the larger second ring gap showed no power improvements below 7000 rpm. The ring gap tests conducted by carcraft awhile back showed measureable increases in power with every amount of reduction in top ring gap untill the rings eventually butted. Engine temperature, load, and piston design I'm sure all have an effect on expansion and the amount of gap needed but running nearest to zero gap at running temperature I'm sure will make the most power. I know of one 4inch bore Chrysler performance engine that runs a .010 top ring gap after much dyno testing. The old 60's chevrolet service manual shows a .013 spec for top ring end gap on forged piston 327's. The Smokey Yunick book I have says don't run less than .003 per inch of bore. Why do the new oem motors run wider second ring gaps?- I'm guessing oil control as the blowby keeps the oil control ring pack cleaner from what I've been told. Big gaps make dirty oil though from what I've seen.
In conclusion I'm still baffled but the next motor I build will be gapped at .004/" on the top and .003/" on the second.


The top ring is subjected to far more heat than the second ring, so in reality if the rings were gapped the same first and second then in running conditions the rate of expansion for the top ring would be far greater causing the gap to close more making the second ring gap seem much larger, right? Bob

A good article on ring end gaps.
http://www.federal-mogul.com/fmeconnect/technicalservices/downloads/1205.pdf#search='speed%20pro%20ring%20end%20gap'

With hyperutectic pistons the gap should be wider than a forged piston. Its best be wider on the gap than too tight and butt the ring set.

I would have swapped the rings around first. It almost looks like your bores are not sized right. Try the #8 top ring in the #5 cylinder and see what happens to the gap.

On a final note from this neck of the woods, I'm fortunate enough to be able to have the dyno and an operator perform testing almost on a 24/7 basis. I could send out thousands of dyno sheets through the years of testing almost every combination that's been tried, pistons, rings, cranks, blocks, heads, etc.
What it comes right down to is this, if a "program" works for you, you stay with it, if not, change is necessary. Just this week I got off the phone with Ross (pistons) and explained they have an inherent design problem in a certain piston they make, they agreed and are going to make a major change, at least this is what I was told. I also know for a fact, behind the scenes, certain mfr's are trying to get more input on the "468 SB" we did. My customers usually end up with money left in their wallets for other things, due to the fact there are certain "cheap" parts that work rather well. I'll give you a quick example, we're able to take those "Australian" heads, which sell for about $900.00 (complete), that almost the entire industry classifies as ""Australian junk" and easily (with 2.020/1.600 valves, NO add'l work on the heads, not even a gasket match on our test engine) produce 445HP/455HP (depending on cam choice), along with superior torque numbers due to the 195 cc intake runners, on any basic Hyd. Roller 383 SB. Thanks for "listening" and "believe half of what you see and none of what you hear". Manufactuers are there for the "bottom-line" only and no more, if the bottom line goes, so goes the mfr. Gary in N.Y.
P.S. Just so as not to make anyone nervous out there on the Ross pistons, which by the way we use quite a few and they're excellent "pieces", the one I'm speaking about is for the old "Nailhead" Buick, of which I'm building a pair of engines at this time. If this was back around 1968, this pistons would be fine, they just need to be updated due to nostalgia engines coming around.

A good article on ring end gaps.
http://www.federal-mogul.com/fmeconnect/technicalservices/downloads/1205.pdf#search='speed%20pro%20ring%20end%20gap'

With hyperutectic pistons the gap should be wider than a forged piston. Its best be wider on the gap than too tight and butt the ring set.

I would have swapped the rings around first. It almost looks like your bores are not sized right. Try the #8 top ring in the #5 cylinder and see what happens to the gap.
that was a good rerad. can someone explain to me why my case ( supercharged ) dosen't go with a larger bottom gap.

If I had a .002" taper in some cylinders could you tighten the end gap up a bit because they say that a .002" taper will increase the gap by .006".

Is that correct and what do you guys think?

Thanks.

If you have .002" taper you better bolt on a torque plate and measure the cylinders.
In this day and age, .0005" taper is the most you should have.
Its also good practice to set ring end gap with a torque plate installed.

I have no idea about the supercharged second ring gap recommendation.

I used to set the top ring at .016" and the second ring at .012" on small blocks.
The last 355 I did we set the top at .022" and the second at .024" and it runs great.

If I had a .002" taper in some cylinders could you tighten the end gap up a bit because they say that a .002" taper will increase the gap by .006".

Is that correct and what do you guys think?

Thanks.
=
Chris,
Is this a used bore? If so you want to set the gap at the bottom of the bore where it is the smallest not at the top.
If you tighten them at the top & it is smaller at the bottom they may butt.
This would also explain why you are seeing the gaps you are.
====
Greg,
I don't understand your question, they do recommend more gap for a blown engine. .006/ inch
=====
cam copier,
Thank you for posting the link :beers:
That is the exact information that was shared at the Fed Mog seminal during the PRI show & at ATEC a few years back.

=============
Bob,
I don't disagree with what was done 40 years ago, I was there too :(
But things do change & if you didn't happen to read the link cam copier supplied here is an excerpt along with a direct link to it:


"SPEED-PRO PISTON RINGS - INSTALLATION GUIDELINES -cont'd


Running with "ideal" end gaps is certainly the goal, but the results of this test show that is better to have a slight amount of additional clearance than to have too little and risk scuffing. When fitting rings to cylinder bores, every .001" change in bore diameter changes the end gap by approximately .003". (Diameter changes affect the gap by the factor of pi…..3.1416").

Example: An increase in bore diameter of .002" increases the ring gap by .002" x 3.1416" = .00628".

RING END GAP RECOMMENDATION GUIDE (FOR 4.000 INCH BORE)
Speed Pro Top Rings

(ductile iron, 4" bore) 4.000" Example Minimum Gap Factor

Moderate Performance .016 - .018 (.004 per inch of bore diameter)



Drag Racing, Oval Track .018 - .020 (.0045 per inch of bore diameter)

Nitrous Oxide - Street .020 - .022 (.005 per inch of bore diameter)

Nitrous Oxide - Drag .028 - .030 (.007 per inch of bore diameter)

Supercharged .024 - .026 (.006 per inch of bore diameter)


Speed Pro 2nd Rings
(cast Iron, 4" bore) 4.000" Example Minimum Gap Factor



Moderate Performance .020 - .022 (.005 per inch of bore diameter)


Drag Racing, Oval Track .022 - .024 (.0055 per inch of bore diameter)


Nitrous Oxide - Street .024 - .026 (.006 per inch of bore diameter)

Nitrous Oxide - Drag .028 - .030 (.007 per inch of bore diameter)

Supercharged .024 - .026 (.006 per inch of bore diameter)

Notice: Most of the second ring gap recommendations are larger than the top rings. Recent testing has proven that a

larger second gap increases the top ring's ability to seal combustion. This larger "escape" path prevents inter-ring

pressure from building up and lifting the top ring off the piston allowing combustion to get by.

Many engine builders have reported lower blow-by and horsepower gains at the upper RPM ranges with wider second ring gaps.


Also,almost every new car made is using this inter-ring pressure reduction method to lower blow-by and emissions and to increase engine output."

http://www.federal-mogul.com/fmeconnect/technicalservices/downloads/1205.pdf#search='speed%20pro%20ring%20end%20gap'ht tp://www.iwon.com/

Wolfplace,

I guess you could say this is a used bore. So If I set the gaps at the bottom I should be okay and the rings should still seat? .002" taper is a accepted taper for a bore?

I would like it to be better but it is pretty hard to do right now.

Thanks for the info.

i noticed that the gaps for both top and second ring where the same when supercharging . so i was wondering why the second ring isn't larger then .024-6.

i noticed that the gaps for both top and second ring where the same when supercharging . so i was wondering why the second ring isn't larger then .024-6.
=
I believe the thinking is .006 is plenty to relieve the pressure between the rings which is the reason for the wider second gap & the top is opened farther because the chamber temp tends to go up quicker with the blower.
Notice the Nitrous is even wider again due to the very fast temp rise.
This temp rise is hopefully not as much at the second ring,,, at least that's the plan :D

That's about as good as I can come up with,,,, :)

BTW, there has also been some pretty interesting theories regarding the oil ring actually working more efficiently with higher pressure above it than what it sees from the crankcase. This pressure is what gets by the second ring.

Well I got some now file fit rings in, made by speed pro by sealed power
.035" over.
I am going to try them tonight.

One other thing I screwed up in posting was the .002" taper because what I was doing was the difference in measurement on the gap between the top and bottom of the cylinder. The taper won't be as much as I posted so I think it will be okay.

thanks for the help.