What I would do is to use the positive deck height spec. with the valve relief specs and then do the same calculation with the piston down .500 with all the other specs remaining the same if you want to know the differences shruggy scope
The first calculation should be accurate shruggy
On your deal using the .500 down with no valve reliefs and then using your actual fill volume will tell you the actual dome volume with the valve reliefs shruggy
I use the .500 down method or what ever depth is needed for hemi pistons to get them below the deck to figure out their true dome volume is up

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)