So I'm building a gsr block with ITR crank and b16 head..... I've searched for hours and found no definite answer. Will Nippon p30 pistons have piston to valve clearance issues with skunk2 tuner stage 3 cams? And also the Zeal compression calculator says my the ratio will be around 11.3 to1. But the site that sells them says 12.1 to 1... what's the known ratio for this setup if anyone here has had it? Any input is appreciated....

 

ttt anybody? Or should i just go with pr3 pistons to stay on the safe side? i would hate to find out later that I could have gone with p30 without a problem....

 

Bump! anyone? I'm ready to order pistons just want to know which are better for my setup

 

Where the experts at???

 

Lol only way to be sure is to check your p2v clearance. There are a few write ups on this site that will tell you how to check. It's a little time consuming but well worth the time also while you are checking on p2v look up how to degree your cams.

 

I'm gonna bet that if there's no reliable info out there, that means it either didn't work and someone is too embarrassed to fess up about their busted motor, or the numbers have been run and it won't work.
It's tough to be a pioneer sometimes
*shrug*

 

Yea... moneywise I'm not in a good position to be a pioneer... so I'm just gonna play it safe and go with the pr3 pistons and maybe a thinner headgasket.... I'm trying to get a high 11 to 1 compression. Plus with the huge stage 3 cams more than likely I would've had clearance problems. Are thinner headgaskets a good idea? Or are they less durable because they are thinner?

 

Well, a thinner head gasket is gonna give you higher compression for sure.
I don't think they're less durable, but don't quote me on that one.
If you HAVE to have higher compression by having the head closer to the block, have the head milled, that way you don't risk popping a thinner head gasket.
There's a few compression calculators you can use that'll give ya an estimate as to your future compression ratio with head milling and all that taken into consideration, but remember that each motor is a little different (and I think you already found the Zeal calculator anyways...*looks up* yep, you did ^^;; )

Well, I entered the shaved head amount of .025 in and it gives exactly 12.1 : 1 compression...so there ya go!
^^