I'm working on getting some new heads from Lloyd and have a question about compression math. Currently my Golen 383 has 11.5:1. That's with 54cc combustion chambers, -16cc pistons, zero decked block, 0.040" gaskets. Lloyd says if I get the 21* Trick Flows with 54cc combustion chambers and everything else the same, my compression will be 10.97:1. Am I missing something here?

 

Lloyd's calculation is correct.
From the information you've given, your current CR is 10.97:1

 

Good to know! Thanks!