decking heads

[militarymustang88gt]

how much more compression would i be looking at if i decked the heads like .040". is it going to be like a 58 going to a 56cc or some thing like that or a little more. just trying to get an idea of how much i am going to need to take off to get to where i wanna be at.

[coupe]

What heads? The volume removed is going to be a simple calculation of the area of the combustion chamber shape (sq. inches) x the .040 (inches)..giving you cubic inches. Then convert to cc.

To get the area of that chamber, I would estimate an equivalent circle radius (squared) x pi (3.14159).

:nice:

[militarymustang88gt]

i just had some e7s i was looking at porting and decking for a little cheap motor i could try and blow up for some fun........ and to see how much hell a rebuilt 50 could take before letting loose.

[coupe]

E7's...I will get a "reduced volume" in cc's (with a .040 cut) for you when I get home. I have some E7's there.

[1Quik85GT]

you need to check and see how far the piston is in the hole!!! getting compression isnt just in milling the heads

[EHardy1971]

You also have to calculate compressed thickness of the head gaskets too. FWIW,I had my GT40's milled .030",which took them from 64cc's to 60cc's,and a CR of 9.8:1.

[militarymustang88gt]

yeah it is a stock rotating assembly i will be using. i am just going for like 10.5:1 then put a 150 shot on and see how long it will last.

[BAD INT]

stock cam?

[militarymustang88gt]

maybe not. not sure.