Restart the rebuild

Yeah it was a head scratcher, I cc'd the valve reliefs and I believe approx 8cc. Trying to calculate for the dome is a little more involved.
Heres some more info I found on Moparts.
Quote
Re: Sealed Power 2332P and TRW L2316F pistons for Mopar 340 engines.

I just took the time to measure the valve relief volume (including the centering hole) in these pistons. This value is 5.1 cc.
Next I measured and calculated the volume of the dome at 0.018” deck height above the block, allowing for the chamfer at the edge, volume = 3.464 cc
The net volume of the valve relief is 1.636cc.
So, the net of the dome and valve relief is the equivalent of a full flat top piston with a deck height of 0.008” down the hole, for calculation purposes.
With a combustion chamber volume of 72 cc and a standard Fel Pro compostion gasket thickness of 0.039”, the actual top of the piston at 0.018” above the block. the C.R. is 9.604:1.
This should work fine with premium pump gas.
The 340 I'm doing right now is for a restoration engine, built to factory specs as much as possible.
End quote
Heres the thread the quote came from.
Old TRW forged 340 piston #2332P
The piston specs should include the dome volume. Include that number as a negative in the calculation.