How much off the head??

[Anonymous]

Well the rebuild of my mustang is not going to make the two week mark. Parts stores have had to special order a large amount of my parts. I wanted it done for prom. Since it is going slower I want to do some head work. I want to mill it but I don't know how much I should take off. I will be now using a composite gasket, and I would like a little bit better compression ratio than stock. Any ideas of how much I should take off, my dad said .030 but I wondered what you guys would think. I'm only doing it b/c I can get it done for freeeeeeee.

 

[Anonymous]

By the way, it is a 1979 mustang with a 200.

 

[Hot 6t Falcon]

Hi Dragula,

The .030 cut will make up for the change to a composite gasket without any increase in compression.

V/8 type people see .030 as a maximum that can be cut, because any more will screw up the angle between the two heads and the intake manifold. We don't have that problem, so you can cut a bit more.

To gain a little more compression, try .070 to .080. I've milled a '75 head .110 to put it on a 144, but I wouldn't recommend that much.

Each .010 cut equals about a 2cc reduction until you get rid of the squish area. After that is gone, you are only making the valve pocket smaller.

Our web site is down for maintinance til about Wednesday, or I'd tell you to go there to run the compression check.

Good Luck

 

[Anonymous]

Thanks for the information.

My question is if it can be milled say .080 with no other modifications.

 

[CZLN6]

Howdy Dragula:

In a word, Yes. You should use hardened steel washers on the head bolts under any circumstances. Be sure to clean out the bolt holes.

Adios, David