They bumper your compression around 11.5:1 with a b16 head. With a gsr, it's slightly more, but I can't recall the c/r exactly since I wasn't concern with that head.
To tell you the truth, my piston aren't "actually" RS Machine pistons (I just say that because it's easier). They are actually Nippon pistons, and damn near identical (atleast appearance wise) to RS Machine pistons I went with these pistons because I felt they were more cost efficient. If I'm paying $300+ for pistons, I want them to be forged and not cast. So those pistons were what I was looking for (a cast pistons that would bump my c/r) and in my price range.
With that being said, I don't know the part number. Your best bet is looking on ebay for those pistons. Another alternative is YCP b20 itr style pistons.





Reply With Quote