[Dark_5.0]

I had absolute hell getting my Ported GT-40 lower to seal off with my Canfield heads so I can feel your pain. I had that damn intake on and off at least four times before I got it right.

what ended up fixing my problem was going from a felpro 1250 gasket to a felpro 1262 along with an @ssload of silicone.

I knew I had a problem cause I was making practicly zero vacuum at an idle. The 192cc runners on my heads swallowed the way smaller ports on my GT-40 lower intake I imagine you are having the same problem.

Bubbles can also mean you have too much oil in the engine. When you have too much oil the crank foams it up.

Good luck,