I would like to know what will my compression ratio be if I had some LS1 5.7 heads milled .20 installed on my car. I plan on using gm head gaskets. Is there a formula to figure this out. I don't remind there being one in the jrp's awesome writeup. Thanks, that was a great write up!

 

10.74 SCR using graphite .054

 

Thanks alot for the quick reply.

 

Actually it is ~ 10.74, sorry
i entered a positive value for piston to deck instead of a negative for out of hole.
My apologies.
I PM's you

 

PM your self with this link so you have it when ever you need it.
http://www.corvettec5.com/CR%20Calculator.htm

 

That one won't work since you can't enter a negative value for piston out of hole.

This is a good one:

http://www.rbracing-rsr.com/compstaticcalc.html

 

Yep the one many of us are now using is the one above and the one in my sig

BTW I got 10.76. If you want to do this yourself.
Go right down the list with these numbers.
3.898
3.622
.054
-.007
0
63.34 (66.67 is a stock head. To figure out the new cc of the head you must subtrack for the mill. A common number used is every .006 milled equals a minus 1 cc. You are milling .020 which would make a 3.33 difference.) (Now take 66.67-3.33 which equals 63.34 and that is the new cc of the heads.

 

Thanks for the link sorry mine didn't work.