First post here so be gentle. I did a search over the last couple of days but didn't find a solution.
I just rebuilt my gm 350, new pistons, rings, block bored .040 over, new cam, lifters, heads rebuilt. The only aftermarket item installed is an Edelbrock intake. Engine has about 500 miles on it. My problem is cannot get the manifold to seal which results in oil burning from the drivers side. What I've done so far.
Replaced intake gaskets with 6 different style gaskets from OEM to Fel Pro.
Installed gaskets with sealer / without sealer.
Bought another Edelbrock manifold and installed.
Installed OEM cast iron manifold.
Pulled engine three times checked angles of all manifolds and heads, re ringed and de glazed cylinders. Everything checked out.
Checked block, heads and manifolds for warpage none found
Checked manifolds and heads for cracks none found.
Replaced valve stem seals three times.

Applied a smoke machine and get smoke coming up into the intake. The intake runners are oily even after doing all the above. It only smokes out of the driver's side, I have a dual exhaust with no cross over pipe. Does not smoke when cold just when it warmed up and only at idle. It goes away when throttle is applied. Does not smoke under hard acceleration. I'm not new to engine building I've done over a dozen SBC and have never had one do this.
Someone please tell me there is a solution to this issue before I douse the old truck in gas and burn it.