One more thing to check is the angle of the intake face of the manifold. I bought a precision protractor like this one:
http://www.use-enco.com/CGI/INSRIT?P...&PARTPG=INLMK3
and checked the angle of the intake surface of the head to the end rail of the block to make sure it is 45* and checked the angle on the intake manifold. I checked my Blue Thunder, Streetmaster, Victor, PI, and Street Dominator intakes. The Blue Thunder and Victor intakes were a bit off by about 10 minutes which I guess is about 1/6 of a degree. They both had a decent imprint on the gaskets but still allowed some
oil to get into the ports. Not enough to cause smoking but there would be some
oil on the spark plug threads and in the ports. The Streetmaster was off by about 1/2 degree. I had a machine shop mill the intake to correct the angle problem on the Victor. I have the Victor on my engine now and it is sealing very well. Another way to check if the head and intake manifold angles match is to place the intake on the heads without a gasket. You can check the gap where the intake meets the head and make sure it sits parallel without the gap getting larger from top to bottom and vice versa. It's amazing how common machining errors seem to be on these intakes.