You can always open up the chambers.
Sink the valves, use tulip shaped valves.
Notch the pistons,changing different head gaskets, all of these things to lower your compression.
It would still be advisable to get your deck clearance closer to .000 = zero deck.
The head on my Camaro now I believe is 82-84 cc's.Trying to remember???
This was for my supercharger.
Prior to this I had the 194 cyl head milled & got 50 something cc's, it's been a while.
So just by swaping heads & head gaskets, I went from 12 to 1 , down to 8.4 to 1 w/forged flat top 307 TRW pistons.
