Setting deck height for 9:1 compression Options

[Chad911sc]

I have my short block built and I’m ready to set my deck height. It’s 96mm bore with stock 71mm factory crank. This is a 2.0 2056 build. I have a Web 86a cam calling for approx 9:1 compression. I have 60cc heads with 3cc valve reliefs on my flat top pistons. If I plug all this into the calculator, I get 8.3:1 for my compression ratio if I set the deck height to .040 inch
After I set up the piston on the rod and bolt down the cylinder to the block, I get .053 inch from the piston to the top of the cylinder.
My question is, what is the best way to proceed to get the 9:1 ratio with at least .040 inch total deck height.
I am thinking that if I take off 6 total cc’s from the head, that will leave me with 54cc heads with the 3cc valve pocket = total 57cc’s. Bringing me now to the correct 9:1 compression ratio with the .040 inch deck height.

If I am in the right ballpark, this means I need to have my heads fly cut….correct??
If this is correct, how do I go about calculating how many thousands of an inch do I need to have removed by the machine shop to remove 6cc from the head?

I obviously will need to remove at least .013 inch total deck height get to my .040 goal, and that’s with no shims or head gaskets being used.

Thanks for your time, Chad

[Chad911sc]

Ok….
Everything is back together after the deck was machined .010 and the heads were fly cut approx .030 to get my head cc total down to my desired 57cc with the valve relief figured into the equation. And yes they also cut .030 off of the ridge on the flat surface of the head so that it would seat fully down onto the cylinder. After assembling the cylinders and pistons without shims, my deck heights varied from—
.035 to .033 on cylinders #1 and #2
.041 to .035 on cylinders #3 and #4
I performed the measurements with a level and feeler gauges at the center of the piston, parallel to the pin. I then repeated the same test with my digital depth gauge magnetized to a steel mounted plate.
I then disassembled the pistons and cylinders and did the exact same tests, using the same piston and cylinder on all 4 different registers. The test shows the exact same results, so that should mean that the pistons and cylinders are equal in distance. This leaves me to think that the new forged rods I purchased must have some discrepancies in their length. Along with bearing differences as well added in there. The rods were supposedly checked and balanced by the seller. I did weight match all my rods and they were within .02 grams of each other.
From my research over the past few days I have found this is not uncommon. Just want to get the best path forward to achieve an engine that will perform and hopefully last.
I know there has to be an acceptable tolerance from head to head so that it will seal properly. And I’m sure there is an acceptable tolerance from one side of the case to the other.
In my head I am reasoning that if I shim one cylinder and not the other to correct the total deck height, it will then make the cylinder head rock on the uneven cylinders since they are all the same height.
So what is my best path forward?
Thanks again for your patience and time….Chad