383 vs 400

demon seed said
Biggest problem with stock block 400's is that the compression was only 8.5 (or slightly lower) with the piston .075-.080" below deck for 200-230HP. When compared to the "stock block" 69-383 you get 10 to 1 with a piston proud of the block by .021" and 335HP. Big difference, this is why I'm more drawn to 383 as the start point.

You get very close to 11.0 compression if you get the piston that far out of the block, all you need to do is stick a head with roughly 78cc chamber and you get 10.0 with a zero deck piston