[Hillard]

Building a 400 block, 4" stroke for the street but also planning on doing some open road racing. Might even try the Texas Mile or something similar. I do plan on driving this car a LOT. Trying to make some decisions on pistons and rings. It will have a Canton pan with the kickouts on both sides. I was thinking of using the Motion Raceworks catch can with breather tubes from both covers going into it to let it breathe. I called Total Seal and the guy told me either 1.5mm top and 2nd, or .043" top and 2nd and go with a 3/16" oil ring. He also said to use a gapless and gas ported ring. My intention is to have custom pistons made from 4032, coated, and maybe DLC coated pins. I want to make decent power and make it for thousands of miles. So longevity is important to me. Any thoughts?

In case you're curious...4.145" bore, Oliver 6.8 rods, KRE 290cfm CNC D-ports, Hyd roller w/ solids 234/244@.050 w/ .560" lift on a 112 lsa. RPM intake and an 800 cfm Q-jet. Planning on backing it up with a Tremec TKX and 3.50 gears out back.

[ID67goat]

Talk to Paul K, he should be able to hook you up with some Racetec pistons with modern ring pack, coated, etc.

[Hillard]

I guess I should add that I'm mainly curious if anyone has experience with the thinner rings, gapless rings in a n/a application, or ported rings.
I can order pistons and rings myself. I know how to get all the math and info they need. I've always used the old standard 1/16", 1/16",3/16" ring pack or the factory ring pack and either Total Seal classic rings or Sealed Power. I just decided to put a LOT more thought into this one. This one is very special to me and I want to make sure it's as good as I can make it. No cutting corners on this one.

[Tim Corcoran]

I had Total Seal gapless rings in my 455 motor, the leakdown rate was less then 2% ran great but had a lot of reversion. I removed them when I refreshed the engine and the reversion went away. I was using a header evac system. Perhaps if I had vacuum pump it may have eliminated the reversion. I think gapless rings may work better with a vacuum pump.

[Dragncar]

I had pistons with 1/16" rings and was going to just run Classic file fits and be done with it. But I got one of my 2nd Sealed Power rings gap too big and getting a hold of Sealed Power tech was impossible.
So I called Total Seal and they were able to sell me a single cast iron 2nd ring.
BUT, I ended up buying a whole new ring set. They were back cut to reduce tension and the top rings are ported.
So this will be new for me too.
Supposed to be worth 7-12HP , why not.
Its only money right !

[steve25]

That statement is a real stretch because I can't see how there's any logical explanation that would allow you can blame reversion on good ring seal!

[Half-Inch Stud]

Originally Posted by steve25

That statement is a real stretch because I can't see how there's any logical explanation that would allow you can blame reversion on good ring seal!

~1992 i had a fresh gapless 455 build that spewed oil. Gapless rings didn't seat. Re-Builder said was my fault for not having (connected or disconnected i forget) the PCV during breakin. CYL walls were a stinking mess. Went with legacy PMG rings since and no blowby on any. Oh and i always run PCV, break-in and all.

Far as i have seen; Gapless rings are for the experienced experts.

[PAUL K]

We use thin ring packs all the time. It's a great way to add modern technology to our beloved Pontiac engines. Machining quality, finish and assembly become more important when using thin rings. They are a win-win at our shop. More power, less friction, less bore wear.

[PAUL K]

Originally Posted by Half-Inch Stud

~1992 i had a fresh gapless 455 build that spewed oil. Gapless rings didn't seat. Re-Builder said was my fault for not having (connected or disconnected i forget) the PCV during breakin. CYL walls were a stinking mess. Went with legacy PMG rings since and no blowby on any. Oh and i always run PCV, break-in and all.

Far as i have seen; Gapless rings are for the experienced experts.

Considering this happened in 1992 I'm guessing thsee were a gapless second ring set. I've heard similar stories that claim due to the increased suction from the gapless ring the PCV system needed to be restricted or it would suck to much oil into the system. Not sure if that is true and not sure if the gapless second rings did much other than improve leakdown test results. I never experienced this on any of my builds using gapless rings and never restricted a PCV valve or removed it during break in.

[Lee]

I've built a few motors with the thin "LS" rings - no problems.

Back in the late 90's I used a set of the Total Gapless 2nd rings. They were basically an iron ring with a groove for 2nd ring (like an oil scraper ring) and you stagger the end gaps. I'm not sure if they even make those anymore, a gapless top ring makes much more sense to me. Anyway, that motor lasted maybe a year, and it was burning oil. One (maybe two, it's been a while) of the gapless rings had cracked. They also had nothing to keep the rings from rotating (maybe they've addressed that issue with their newer rings) and several of the other had rotated so that the gaps were aligned (so no longer "gapless").

[PAUL K]

Originally Posted by ID67goat

Talk to Paul K, he should be able to hook you up with some Racetec pistons with modern ring pack, coated, etc.

Thanks for the referral

Originally Posted by Hillard

I can order pistons and rings myself. I know how to get all the math and info they need. .

Part of that information will be the ring pack.... Lol

[slowbird]

Originally Posted by PAUL K

We use thin ring packs all the time. It's a great way to add modern technology to our beloved Pontiac engines. Machining quality, finish and assembly become more important when using thin rings. They are a win-win at our shop. More power, less friction, less bore wear.

Totally agree! But the pistons and rings need to go together, people are better off talking to an experienced person (like you) to order the pistons and rings through so you know they'll work.

[PAUL K]

Originally Posted by Lee

I've built a few motors with the thin "LS" rings - no problems.

Back in the late 90's I used a set of the Total Gapless 2nd rings. They were basically an iron ring with a groove for 2nd ring (like an oil scraper ring) and you stagger the end gaps. They also had nothing to keep the rings from rotating (maybe they've addressed that issue with their newer rings) and several of the other had rotated so that the gaps were aligned (so no longer "gapless").

I saw the same thing after taking a couple of engines apart, the two piece ring set up aligned itself so there was a gap. Careful finish on the ring ends will prevent the rings from aligning... Most of the time.

The Chids & Albert design was much better than Total Seals.

[Half-Inch Stud]

Yea, my "lesson learned the hard way" was Total Seal's Gapless 2nd ring. Total Swill

Used the Chevy thin stacks in the 455 with good results.

[cfmcnc]

How many NHRA ProStock engines are running gapless rings,How many Nascar Cup engines are using gapless..I know the answer!

[Hillard]

Originally Posted by PAUL K

Part of that information will be the ring pack.... Lol

Yep, along with how far down to put the 1st ring, valve sizes, valve angle, valve drop, rod width, thickness above the pin, pin diameter, etc etc

Originally Posted by slowbird

Totally agree! But the pistons and rings need to go together, people are better off talking to an experienced person (like you) to order the pistons and rings through so you know they'll work.

It's been a very long time since I've posted on here. There used to be many experienced people on here. Hopefully there still is??? I'm just trying to gather information from many sources to educate myself on all the different types of rings, and what works best in certain applications. I've built a LOT of Pontiacs but I admit I had a couple different brands and types of rings I stayed with. Sure they worked, but were they the best for the application?? For this particular engine I want to do my best to make sure everything works together, and is as good as I can put together. I'm not going to strictly use what one person says, whether it's on here, another builder, or manufacturer. Right now I'm leaning towards Diamond Pistons and will most likely purchase the Total Seal rings I want through Diamond so that they know exactly what I'm working with. But it's not set in stone.

[Hillard]

Originally Posted by cfmcnc

How many NHRA ProStock engines are running gapless rings,How many Nascar Cup engines are using gapless..I know the answer!

Well I'm not building a Pro Stocker. I am building an engine for more endurance, so maybe closer to Nascar. But I'm using a wet sump, not a dry sump. Not using a vacuum pump either. Also going to drive it on the street quite a bit. It all makes a difference in selection. I know Pro Stock and Nascar use (or have at least used at one time) a one piece oil ring. Probably would not be a good choice for me. So not sure that there's really much comparison here.

[slowbird]

Originally Posted by Hillard

Yep, along with how far down to put the 1st ring, valve sizes, valve angle, valve drop, rod width, thickness above the pin, pin diameter, etc etc




It's been a very long time since I've posted on here. There used to be many experienced people on here. Hopefully there still is??? I'm just trying to gather information from many sources to educate myself on all the different types of rings, and what works best in certain applications. I've built a LOT of Pontiacs but I admit I had a couple different brands and types of rings I stayed with. Sure they worked, but were they the best for the application?? For this particular engine I want to do my best to make sure everything works together, and is as good as I can put together. I'm not going to strictly use what one person says, whether it's on here, another builder, or manufacturer. Right now I'm leaning towards Diamond Pistons and will most likely purchase the Total Seal rings I want through Diamond so that they know exactly what I'm working with. But it's not set in stone.

Well I've ran 1mm rings, .043, and 1/16 with gas ports in rings. All very good and have their place. Personally I wouldn't run anything thicker than 1.5mm. .043 seems to work real good and will last a while imo.

[PAUL K]

How long they last is a big consideration. Also what's available at a reasonable price plays a factor in my world. Some of the metric rings are custom for some popular Pontiac bore sizes from one manufacture (I should say re-seller) and a similar set is considered a shelf item with another and it sells for almost half the price.

[PAUL K]

Originally Posted by cfmcnc

How many NHRA ProStock engines are running gapless rings,How many Nascar Cup engines are using gapless..I know the answer!

That's easy.... What are the guys using that are stuck with fifty year old seasoned blocks that have cylinders that flex a lot?