Milling a Mopar flathead...How much to cut?

I'm going to have the head off of my '55 Plymouth 230 soon. I figure since it's off anyway, I could have it shaved. How much can I cut to get a little more performance. Thanks.

-Jeff

 

Don't cut anymore than is needed to clean it up. .010 is good to start, then when you get the engine assembled, clay the heads. Check how much more you can take off then cut more. Never cut off a lot then try to fit the head, you might have taken off too much and that is a LOT bigger problem then not taking off enough. Always clay your heads, then mill it to the clearance you want.
Mike