Intake Leak

teringer said

I think your going to trace it back to bad machine work ,possible wrong angel cut some were another note are your intake bolts too long bottoming out giving the appearance of being tight with all that cutting on everything or the shoulder bottoming out on the bolts, just another thought. also check to see how tight the bolts are going through the intake manifold you may need to open them up some to let the intake move smoothly when torqued down and not bind .

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X2 I always thought for every .010 you took off the block you take .012 off the intake.
I would say your intake or heads are milled crooked.

FYI I used a metal gasket on my un-milled 318 in my truck with a old un-cut LD4b intake.
Even using copper spray gasket on the metal gaskets, it started leaking in a couple of weeks.
Put a premium fel-pro gasket on it, I think it was around .030 thick, copper sprayed it. The bolts were a complete ***** to get in, but two years later it does not leak.

Apparently my intake was not manufactured straight, and if a machinist just run a dial indicator across the edge of yours, it most likely is not square with the heads.

You can pick up a cheap angel finder at any hardware store, and check head, vs intake angle, use copper spray on the intake it really works.