I just had a 396 built and they shaved .020 off the heads. Should they have shaved something of the stock intake manifold? They told me that they had checked and it will be fine without taking anything off.

I have heard (don't know if its true though) that .020" milled off the deck is about the max that you can take off without having any taken off the intake side.

I had .040" flat milled off the deck of my 049 oval ports and the machine shop took .020" off the intake side. Everything lined up with no problems.

Are there any downsides to machining material off the intake side? I think I want to mill my heads on my 454 to bump the compression a little more, and I know I'll probably have to get the intake side machined as well.

I had my heads milled .020, no probs with the intake sealing graemlins/thumbsup.gif