Has anyone figured out yet what compression ratio loss would be if 6g75 heads put on 6g74?

Hope this helps.
http://www.aussiemagna.com/forums/showthread.php?t=89946&highlight=

Just go 3.8 Andrei, its way better!!

yea for sure, compression drop is way too much, you would need to run of about 14 psi boost to make it beneficial