Rings for 4.1 - 0.030 over (3.995" bore)

[dlafont]

I need a sanity check..

Just about to order the following ring set from JEGs:

Total Seal JM4000 Total Seal OE Quality Piston Ring Sets

They are for a 4.000 bore.. I assume that I can just file fit them?

Thanks.

 

[Nick Micale]

Just my opinion, but why would you NOT order a performance set from Total Seal that would be an exact fit and suited for a higher HP level than stock, daily driver needs.

We just replaced a trashed set of 4" bore rings in a 3.965" bore after 12 passes.

These were file fit to work by another shop - NOT. It was blowing a pint of oil out the breathers every pass.

You CANNOT build these engines, or any make, with cheap parts instead of the proper parts for the job.

This was a mistake that cost over $1000 just for shop work and parts besides the R and R.

 

[dlafont]

Nick,

Thanks for the input.. I am definitely not wanting to be on the cheap especially for rings however I have gone through a gazillion threads on this board about different rings that are good or not. I'm looking for a set of rings that are proven for my JE piston and bore setup. 3.995 bore 4.1 - 291 block.

I know you've built lots of 4.1's so what rings do you recommend? Part no?

Ive got the 10sec. Shortblock but just putting it back together with all the appropriate parts.

Don

 

[Nick Micale]

Nick,..................I know you've built lots of 4.1's so what rings do you recommend? Part no?

Don

We are fortunate to have a Total Seal plant locally, and they have a wealth of info on turbo builds and they also make special ring packages when we need something special.

You should call them direct to discuss your build and they supply exactly what you need.

 

[lazaris]

Go with their AP steel ring with PVD coating on top with a Napier second.

 

[dlafont]

Go with their AP steel ring with PVD coating on top with a Napier second.

Called total seal.. Without something custom (lots of $$) they only had moly top ring, cast second ring. They mentioned gapless for the second ring... Anybody vouch for the gapless? Not sure I like the sounds of a gapless 2nd ring..

D

 

[lazaris]

Called total seal.. Without something custom (lots of $$) they only had moly top ring, cast second ring. They mentioned gapless for the second ring... Anybody vouch for the gapless? Not sure I like the sounds of a gapless 2nd ring..

D

Who did you speak with? I have the AP steels for a 4.00 bore on mine.

 

[dlafont]

Who did you speak with? I have the AP steels for a 4.00 bore on mine.

Dont know who I talked to.. Just a guy from the technical dept. He looked it up and said he didn't have them in the 5/64" top, 5/64" 2nd and 3/16" oil ring. What ring thickness are you using? Also... 3.995" is close to 4.00" so my thinking is that a 4.00" ring can be file fit to 3.995" bore.

 

[lazaris]

Dont know who I talked to.. Just a guy from the technical dept. He looked it up and said he didn't have them in the 5/64" top, 5/64" 2nd and 3/16" oil ring. What ring thickness are you using? Also... 3.995" is close to 4.00" so my thinking is that a 4.00" ring can be file fit to 3.995" bore.

Ok thats the problem. The 5/64's they do not have. I'm using a 1/16" I think your stuck with a moly. However ask Total seal if they have the spacers for their 1/16 rings. They might have that as an option.

 

[turbofabricator]

Go with the moly top ring and STD second ring. Gapless second rings tend to cause ring flutter under high boost. Open the second ring gap a few thousandths more than recommended. Too much is way better than too little. Opening the second gap allows better trapped end gas bleed and helps prevent top ring flutter under high boost. The second rings primary function is a secondary oil scraper not compression seal.

 

[norbs]

Here's an older article on rings, might help you decide what to use.

Piston Ring Tech - The Latest Developments In Cylinder Sealing - Hot Rod Magazine

 

[dlafont]

Go with the moly top ring and STD second ring. Gapless second rings tend to cause ring flutter under high boost. Open the second ring gap a few thousandths more than recommended. Too much is way better than too little. Opening the second gap allows better trapped end gas bleed and helps prevent top ring flutter under high boost. The second rings primary function is a secondary oil scraper not compression seal.

Yes... That's what I heard. What about using a gapless top ring?

 

[dlafont]

Yes... That's what I heard. What about using a gapless top ring?

Anybody? Gapless top ring worth using? Experiences?