I need to know if its true that a gsr motor will receive less compresion with a type r head... If so how much less?

 

Yes. .3 less.


Don't swap heads unless yours is ruined. The gains aren't worth the price you'll pay for a type R head.

 

Yes, but .3 sounds a little low,
I have a GSR head on a B16A, so my C/R is about 10.6-10.7
Considering a stock B16A is 10.2 (B16A1), the head should drop your C/R about .4-.5, max.

 

I already have the head... The reason i asked was because i'm planning to get some high compresion pistons. I was looking at some JE 12.5:1 for gsr. and to my understanding 12.5:1 is a little too high for pump gas. Since i have the type r head on a gsr my compresion should be somewhere around 12.1:1. Correct me if i'm wrong....

 

anybody??

 

It would depend on the octane of pump gas in your area. 91 octane, no I wouldn't do that. 94... yes, with good tuning.


But if you're buying aftermarket pistons just get some 12.0:1.

 

Right, your correct about the C/R, it'll be around 12:1
But if u don't run AT LEAST 93, prob need even 94 or more
That's getting pretty damn high, Maybe u should shoot for around 11.5:1 or something.

-Mike

 

what do you consider good tuning??