On olds (specifically 425 ,66 in this instance )are the head and intake angles zero ?? If so and I mill the heads x then would I have x taken off the intake ??
cheers in advance
mike

 

I think you are better off take it off the intake side of the heads, not the intake it's self?

 

All 64-90 Olds heads have the intake surface at 90 degrees to the deck surface. The intake angle does not change when the heads are milled. What does happen after milling the head is that the ports in the head are now that much lower than the ports in the intake. Milling the intake or the intake surface of the heads lets the manifold sit down closer to the block and thus eliminates this mismatch. Each side (or head) needs to be milled by the same amount as the deck was cut for the geometry to be restored.

 

Cheers for that --je le comprend

 

ooooh thanks