Hey!
I need to decrease the distance from the quench blocks on my pistons (440) to the open chamber head flat. The piston flat is down .030" in the block, so I can't decide whether to zero deck the block or just mill the heads the .027" I need to get my .035" squish/quench with a .022" steel shim head gasket.
Do you have an opinion on this? I have measured everything with dial indicator and burette, so am confident in my numbers.
This is just a hot street engine in a '69 Dart, approx. 10.5:1 depending on the final volumes, iron block and heads, forged steel h-beam rods with floating pins, and KB Hyperutectic quench block pistons, .509" 292 old school cam.
Thanks!

How deep are the dome recesses in the heads, and are all of them exactly flat and parallel to the deck?
Neither of those operations without this.

Block and heads have been machined and checked.
Open chamber recess is .0850"
I know my numbers are spot on, just can't decode on which to mill. If it really doesn't matter then I will do the least expensive.

If its a 2.06"-ish CH piston, then deck the block to get the piston to zero deck. This will work with the most other pistons, and will work with all future closed chamber head. If you want more compression now, take the rest off the heads. Keep track of your numbers to mill the intake side accordingly.

2.063" to be exact.

That's the missing piece I was looking for. Deck the block it is. Thanks!

If I zero deck the block and run a .027" Cometic I will have .037" Squish/Quench, perfect.

He is running a quench dome piston.

My vote would be to put it together and run it. You will never know the difference. My opinion is why compromise the deck thickness or cylinder head thickness when I bet it won’t matter. My personal opinion is that if you can get good quench great it’s piece of mind. Bit if it’s not convenient I wouldn’t bother. I think that it is over rated, especially with a open chamber head.

I agree.