Had the same problem with E Street Heads and a Weiand dual plane on my 383/432 Stroker

Block was not cut , just cleaned up resurface - Made it clear to the machine shop

Used these gaskets on the head side of the valley pan , dry silicone bead side to the heads and ports then Edelbrock Gasgacinch to glue the gaskets to the bottom of tin pan itself

http://www.hughesengines.com/Index/...EJsb2NrIChMb3cgRGVjayk=&partid=33979

Intake manifold side of tin valley pan no gaskets

Has worked awesome so far this summer

My latest set of NGK 6 look great with no oil use

Makes you wonder how much of that oil if any works it’s way through the exhaust system ? Was going thru about a quart every 500 miles or so for a few summers