Shaving

I beg to differ. I had a 69 dart with a 225. Bought this thing with a badly warped head. It took .100" to make it flat. I chased out all the threads in the block and blew em out with compressed air, cleaned the bolt threads on a wire wheel on a bench grinder. Then on installation, i installed the bolts with a small amount of oil on the threads to effect a proper torque. This engine popped 2 head gaskets in a short period of time after that. Ended up having a machine shop buddy of mine knock 1/8" off the ends of the bolts before I installed head gasket #3.

After that, I had no head gasket problems. What was happening was The bolts were bottoming out and providing barely enough clamping force, and the gasket would be fine for a very short period of time, then it would pop. Maybe my block was not drilled and tapped deep enough from the factory, but removing a bit from the threaded end of all the head bolts seemed to correct the issue with as much as I had to have milled off the head. BTW that .100" milled seemed to give her a little more getup and go as much as one can get from a stock 1 barrel slant sux.