I need help on estimating the CR my car would have after this, I beleive the cometic gasket I have is lowering my CR but I haven't found any other in 81.5mm

I have Arias High Compression Pistons which claim to raise to 11.3:1 in some websites, and 11.5:1 in some other website. That would be on a stock gasket I supose, which is about 0.7mm,(0.0275"). My gasket is a cometic with 0.030" thickness, I think I might be loosing something like 0.1 of the Compression Ratio, but ok thats not the problem right now.

Tha problem is I'm getting some flat faced valves, which should raise about 0.2 or 0.3, right? And I think I will have once more the cometic head gasket in 0.030" thickness, so the question is;

How much should I mill the head to have a 12.0:1 CR? having the following setup:

Arias High compression Pistons
Omni Flat Faced Valves
COMETIC 0.030" head gasket.

My guess so far is that milling 0.010" won't make it, I think it might get somewhere beteen 11.7-11.9, depends on the arias pistons info.

Thanks.

 

its not a good idea to mill the head you should have just gotten 12-1 compression pistons and have been done with it, now you want to change valves and mill the head just to get some more compression, if anything try a 1 layer headgasket but dont mill the head

 

the head needs to be milled, or resurfaced i don't know the exact term, but I had a problem with the radiator and my car overheated, one exhaust valve failed and the head had a little injury that can only be solved by milling, from what they have told me the required mill to straighten the head is about 0.008" so I thought 0.01" would work perfect and raise my compression that bit I wanted to get to the 12.0:1

by the way, why do you say not to mill and go for a 1 layer gasket, first, I have no choice but to mill the head, and second where can you get a good 1 layer gasket that can hold the 12:1 compression?