At the moment I have a gsr block with wiseco 11.5.1 piston and a b16 head. I would like to get the compression up to 12.1 or more, will a 2 layer HG get me somewhat close or am I going to have to mill the head a bit?

 

raising your CR by a half point is not even worth what it would cost to buy a new HG, and put it in.

im sure thats not the answer you are looking for and i am sorry but 4 or 5 people are about to come in there behind me and say the same thing.

but yea, just buy an OEM HG, opo the rivets out and pull the silver middle layer out and put it back together and youll be close to where you want to be without breaking out the calculator, or if youre me, crayon and napkin.

 

ull gain .2 to .25 Max gain in compression, if u can install CTR pistons in that motor ull get above then that ur looking for,

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by salman &raquo;</TD></TR><TR><TD CLASS="quote">ull gain .2 to .25 Max gain in compression, if u can install CTR pistons in that motor ull get above then that ur looking for,
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which thread did you read that in?

 

1mm =1 CR approx.

Stock head gaskit = .75mm

Do the math,

 

god here we go again. what cc are the pistons? whats your PTDH? how big of bore are these pistons? whats your combustion chamber volume? what stroke are you running?

i hate to sound like a broken record but your probably in the 10.?:1 with those pistons. my old JE pistons were RATED 12.5:1, but upon doing the math with incorporating the bore size, combustion chamber volume, PTDH, stroke, and cc of the dome the pistons were actually 11.3:1.