Cp Ring Gap

[adamsrotor]

hey, im about to set my ring gap on my rb25 and would like some opinions from you guys. im using cp's with 40 thou over pistons. cp reccommend bore x 0.0065/0.007 for top ring, bore x 0.007/0.008 for 2nd and min. of 0.015 for oil.

my bore is 3.425'' so top works out at 0.023, 2nd at 0.0274.

is this suitable or is should i be running something smaller. thanks.

[The Dan]

The calculation comes out at 22.2thou so 23 or 24 will be fine

For the second ring 26-28 will be fine at that bore size. Do not go smaller and add 1.5 thou for every 100 shot of NOS you are running if applicable.

[adamsrotor]

The calculation comes out at 22.2thou so 23 or 24 will be fine

For the second ring 26-28 will be fine at that bore size. Do not go smaller and add 1.5 thou for every 100 shot of NOS you are running if applicable.

thanks very much for the info.

[T04GTR]

umm, id take 5 thou of that. for both. there gaps are a little big for a street motor.. somwhere around 15 and 18 is fine.

[2rismo]

Is this a street or race engine?

[Swiper the Fox]

umm, id take 5 thou of that. for both. there gaps are a little big for a street motor.. somwhere around 15 and 18 is fine.

correct...the ring gaps quoted by Elite are excessive to say the least.

i wont quote what ring gaps i use but some where around or near to whats quoted above

[The Dan]

correct...the ring gaps quoted by Elite are excessive to say the least.

i wont quote what ring gaps i use but some where around or near to whats quoted above

Great! so now you know more than the piston manufacturer. Congratulations.

I just hope this guy has the good sense to not listen to your comment and instead listen to the people who make the piston and rings.

But hey, I could be wrong. While you're at it, give him your rule of thumb on piston to bore clearances. We wouldn't want him making the mistake of using the piston manufacturers specs on that one.

[2rismo]

Giving any advice without knowing the proposed use of the engine is plain retarded.

[The Dan]

Run them where you/he likes...its your/his engine

ask my customers have they ever had a problem with an excessive breathing rattly engine when using CP pistons.

my piston to bore clearances are none of your business...i don't want to give you any more free advice.

Yeah nice.

But when he cranks the boost up and binds the ring ends because you told him to run 17thou, how are you going to explain that to this guy. If you don't follow the instructions made by the manufacturer then you are asking for problems. Or do you just choose the information you adhere to or not? I don't really care what piston to bore clearance you run and I certainly don't need your advice. I just think you need to think about the consequences of giving advice like that in a place like this.

[Swiper the Fox]

Great! so now you know more than the piston manufacturer. Congratulations.

I just hope this guy has the good sense to not listen to your comment and instead listen to the people who make the piston and rings.

But hey, I could be wrong. While you're at it, give him your rule of thumb on piston to bore clearances. We wouldn't want him making the mistake of using the piston manufacturers specs on that one.

Run them where you/he likes...its your/his engine

ask my customers have they ever had a problem with an excessive breathing rattly engines when using CP pistons.

my piston to bore clearances are none of your business...i don't want to give you any more free advice.

Edited October 7, 2008 by DiRTgarage

[The Dan]

Giving any advice without knowing the proposed use of the engine is plain retarded.

In a way yes, we have not yet established if his engine is turbocharged or not. So that would be a start.

[The Dan]

....and I wouldn't call 28thou excessive in a 3.425 inch bore. People cringed when engine builders started running closer to 3thou BE clearances but it was all for a reason. Ring technology these days is that far advanced from the 90's. You don't need to run tighter end gaps to keep it sealed.

[FineLine]

After seeing how well my engine stood up to the work i put it through before the clutch explosion, I am not arguing with 3lit3 32. I dragged it, raced it, and generally did all you can do in a high performance car. On teardown the piston.s rings. and bore.s were still like new. He built it and is building the replacement and i wouldnt have it any other way.

[adamsrotor]

ive already done them to elites spec. and yeah its also what cp reccommend so cant be too wrong. just wanted to double check. last thing i want is the rings binding. and yeah it is turbo (garrett t04z), planning on running high boost. street car but will be seeing the track a fair bit! thanks again.