How much can a cast iron oval port head be milled? I don't have a compression rule, so I'm looking to mill as much as I can to maximize the compression. Also, what about angle milling the head, any thoughts there?
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How much can a cast iron oval port head be milled? I don't have a compression rule, so I'm looking to mill as much as I can to maximize the compression. Also, what about angle milling the head, any thoughts there?
I'll bet if you put the words "head milling" up in the search box you'll probably get some pretty good results. :)
The maximum we would recomend as a starting point would be .150" off of a NEW head. The factory thickness is roughly 3.800" from the valvecover rail to the deck of the head. We have done some heads .175" off by installing studs in the lower intake manifold bolt holes before we milled the head. We have also seen the chambers collapse from being milled too far...Quote:
Originally Posted by pinto99
As for angle milling, unless your capable of re-cutting the valve notches at the new angles, don't angle cut the head...
Cheers,
WiseCo Pistons also has a 2300 aluminum piston with a relatively small 7cc dome. If the dome is slope-milled from the exhaust side upward to the peak of the intake side, the remaining portion of the dome will contain 3.5cc. That will raise your geometric compression ratio ~(1) point. Say..... from 11:1 to 12:1. And the slope-mill will force/'pump' the incoming mixture from the induction toward the center of the cylinder, which improves flame travel when the mixture is ignited. -Dave-