Hello, Michael

I'm rebuilding my L98 to a 355. The guy I bought it from, had machine work done on the heads. He gave me the paperwork from the machine shop. They were cut for 2.020/1.600 valves, they were ported, and then I saw that it said that the heads were milled 0.80 and the intake (3 sides? don't know exactly what that means) were milled 0.80 also. I'm thinking that this was done bc when the heads were milled, the valley gets narrower, so the intake side of the heads needs to be milled too, to compensate? Am I correct? I'm just wondering if this is going to affect the fitment of my intake? I'm thinking it won't seeing that the heads were milled evenly all around. Am I correct?

Apeiron

When the heads are milled the intake ports get a little "lower", closer toward the block. If it's a significant amount, some material is milled off the bottom and the two port surfaces of the intake to match.

Hello, Michael

So I won't have a problem lining up the ports on the manifold with the ports on the heads?

Apeiron

Best way to find out is to try it.

bwiencek

I'm guessing that the heads were "Angle Milled" with .080 coming off the exhaust side then the intake side was milled back to the proper angle for intake sealing.

best thing to do is mock up the head and intake and get a camera or if it's a straight intake you may be able to see and check the port alignment. Another "quickie" way to do that is to tape a gasket to the intake lined up, then bolt it down and transfer the tape to the head side and carefully remove the intake and see where the gasket lands - not real accurate but a LOT better than doing nothing and just assuming it's fine...