Compression ratio?
How far down in the hole are they @ TDC or are they sticking up and out ???
What gaskets are you using ??? What CCs are your combustion chambers ??
Where those heads CNC’d and/or milled ??? What compression ratio are you after ?? What is your use of this engine ??? What octane fuel do you have available or plan to use ???
It’s really a tad bit more involved than Just a 402 with LS6 heads
That link is a calculator and has all of the parameters needed for finding the compression ratio. Plug away.



