Ring gap question

[but]

I am using .020 over ross pistons,and This motor is going to be run on 18psi of boost as a daily driven car.Sometimes It will be pushed to 25psi. What is good clearances for the rings? I read alot of different answers.

 

[killer_eclipse]

i run 20 psi daily and as high as 25... I'm still on OEM spec for my ring gap with no problems.

 

[1995gsx20g]

to be honest i wouldn't leave oem spec's unless the car has one sole purpose.
but there is nothing wrong with riding the better limit within the specs.

 

[but]

Since The machine shop did all the work I shouldnt have to measure ptw clearance,just end gap correct?

 

[mjag60edsm]

it's best to ALWAYS check the machine shop. Throw a rod or bend some valves, take your engine to the machine shop and ask for them to fix it... bet you get an un-wanted answer. I concur with the other folks... OEM specs on ring gaps.

 

[1995gsx20g]

+1 what he said. trust no one.

 

[but]

Well I dont have a micrometer to check.

 

[2GRick]

Well I dont have a micrometer to check.

+2 Trust no one. You may be able to rent one from a rental yard. It's a great education and you'll be a lot more confident and knowledgeable in the future. After all thats part of the reason you bought the car right?

 

[half-cocked]

No, its not OEM if your using ross rings, I have the same pistons.

Heres the instructions.

http://www.rosspistons.com/information/racing_rings_installation.pdf

Disclaimer, I dont remember what the OEM specs are. I just knew Ross has their own formula for it.

Ok the link I posted wont work when I click it so I'm turing this into a cut and paste party.

END GAP
ROSS RACING RINGS for the top and second grooves are oversized
and must be file fitted to obtain proper end gap.
The proper amount of end gap required is directly dependent upon
the amount of heat to which the top ring in most cases should be the
bore size in inches x .004. (To convert mm to inches multiply the
bore size in mm x .03937). To determine the proper end gap in the
second ring on normally aspirated engines multiply the bore size in
inches x .005. It is recommended that the second rings have more
end gap than the top rings to allow any blowby gasses passing the
top rings to quickly escape to the crankcase. If the second ring gaps
are set smaller than the top ring gaps, the engine may show less
leak down under static conditions! Should the top ring land be .180
or narrower add .002 total to the above computed end gaps.
EXAMPLE: 3.625 (92mm) bore with. 150 width top land: 3.625 x .004
= .015 plus .002 for the narrow top land = .017 total end gap.
For engines that are blown, turbocharged, or run nitrous systems of
more than 30 horsepower per cylinder add .004 total to the end gaps
shown above. EXAMPLE: 3.625 x .004 = .015 plus .004 for
turbocharger - .019 total end gap.

 

[killer_eclipse]

well according to your post his no. 1 compression ring needs to be at .0142 correct? And his no. 2 compression needs to be .0182? if so these numbers are still within factory spec.

 

[half-cocked]

I put a disclaimer up, I knew ross had there own figures I just dont remember the OEM specs. Regardless he should not have been told "just put it to OEM specs" if there is a manufacture specific formula out there.

 

[1995gsx20g]

I put a disclaimer up, I knew ross had there own figures I just dont remember the OEM specs. Regardless he should not have been told "just put it to OEM specs" if there is a manufacture specific formula out there.

i understand where you are coming from but not many of us use oem pistons either..