If I have 11.0:1 CR piston, how much should I shaved off the block to get to 12.0:1 Cr

 

you'd never be able to shave that much off without knocking your valves. unless maybe you got new cams that had about half the lift of stockers..but in that case, you wouldn't see any increase in hp.

to make a jump in compression like that, try new pistons, or overbore, or skunk2 flat bottom valves or something like that.

 

.030" if it hasnt been shaved already

 

when you start shaving alot off you have timiming belt fitment issues...

Blaze

 

u mean milling.

 

or if its the block then decking...

 

I'm close to .040 and I'm running on 11.0:1 pistons, No valves problem here, just a little detonation at first, but I tuned it out