how much can be milled off of c heads before you have to mill the intake manifold is .030 to much and also how will that affect the comp. ratio  carl

Carl:

.030 would probably not require milling the intake surface since you will probably have to use composition gaskets instead of steel shim.  It will keep the compression ratio close to what it was before.

John

John - "The Hoosier Hurricane"

Decking the block comes into play as well. When you have the heads torqued set the intake with gaskets on the engine and use a flashlight to see how the bolt holes align with the threads in the heads. This observation will give you an idea where it is. I believe the holes in the head should fall slightly below center of those in the intake. This way they become centered as the intake is torqued.


Lawrenceville, GA