I was woundering how many compression points dose. .020 of milling achieve. And how much is safe to mill a gsr head on a stock b20 bottom end. I'm only trying to achieve a 11-11.5:1 on a b20 vtec with a gsr head wit a 2 layer head gasket. So how much would I mill the gsr head

 

https://zealautowerks.com/bseries.html

 

Milling the head is a really bad idea. You get a bump in compression, but it is hard to tension the timing belt AND you increase the chances of valve to piston contact. The bottom line is if you want more compression, put pistons in it.

 

Get some oversized Nippon B16 P30 or ITR pistons and get the compression you want.