We are fitting the rings to the cylinders right now and wondering what everyone recommends? SRP says that for high performance street put the top ring at .018 and the 2nd ring at .020. However the moderate turbo/nitrous recommedation is .020 and .022.

This is a 383 that will be mostly n/a with nitrous on it later. 200 shot. I talked a little with bret and he told me the nitrous needs a bigger gap cause the rigns expand. I believe him, but just lookin for some personal experiences. Ive also been told that the top ring should be bigger than the 2nd.

 

I set mine @ .023 n/a and plan on shooting a 100 shot. What rings are you running. I am running cast.

 

2nd rings are a cast iron/phosphate
tops are ductile iron with plasma moly

srp pistons, JE pro seal rings.

 

I went .018 and .020 but I dont plan on anything over a 150 shot.....you may want to go .020 and .022

 

any big effect on n/a performance? i have no choice, but just wondering.

and we already gapped the bottom rings to 18 what a bitch!

 

just talked to a "tech" at srp and they said 20 on top and 22 on the bottom.

I suppose having more gap is much better than having not enough

EDIT: I guess i dont think srp is wrong with teh gap specs, its just is 200shot of juice considered moderate nitrous? or should i increase the gap even further than 20/22?

 

we gapped them at 18 and 20. I dont really think ill be spraying a 200 shot anytime in the near future, and by then the rings should have opened up a little bit anyways.

builder, who i trust since he does know wtf is going on, told me that since i am not planning on nitrous anytime really in the near future, that the rings would wear and open up to the bigger gap, while giving me the increased life of the smaller gap motor.

This sound right? Will it be ok for a 150 shot? That should put me deep 10s which i would be happy with................for the time being

 

150 shot will be fine. Going deep 10s will depend on alot of other powertrain variables.

 

i think a low 10 (10.2or3) is fesible on a 150shot with a built stroker.

Forgot to mention that i am at 5200ft altitude, the track is at 5800, and the DA on a mother****ing hot day like today is like 11-12000 ft.

 

I wouldn't settle for "good enough" when you're talking about playing with N20 down the road. If I were you I'd get another set, use the old set as a learning experience, take your time and do it right NOW before it bites you in the butt down the road. It either will or it won't, but would you chance a cheap set of rings over your entire motor? This has happened to me in the past.

- Brent

 

the rings are still good, they would just need to be filed more.

anyone actually running nitrous on a smaller gap have any input?

 

Ahhh, yer right!! I was thinking the OPPOSITE for some reason. Brain fart. Mah-BAAAAAAD...

 

.020/.022 sounds like a good spec... even going wider (.022/.024) isn't gonna make a hill of beans. For a nitrous motor, you'd rather be too wide then too tight.

But on the spec, it depends alot on where the rings are located on the piston (how far they are from the combustion). The thickness also plays a big part.... then there are other factors.

Good luck.

-Mindgame

 

how will 18/20 perform? will a 150 shot work?

he said that the extra gap will decrease motor life by about 40k?

the pistons are SRP p/n 139628, im gonna try to findspecs on the ringland thickness, etc.

EDIT: Whats stock gap? will 2 thousands of an inch make that big a difference? How much do the rings expand?

 

40k miles? no way


set them on the high side of NA specs/low side nitrous. it will be fine.