As Christopher Walken would say...........
...'Wowie wow, wow wow...........
.........I never cease to be amazed at how defective the human gene pool can get.
Running exhaust inside the car?
??
I too threw a 4 bbl. adapter up on top of an EFI lower and thirty seconds later it was no, non, no, no............
.......no. Kinda silly anyway, the engines just really can't use a 4 bbl., the 4 bbl. used is artificially super small so not really one anyway. These run better with 2 bbl. to me, even in race configuration. I think the Offy 4 bbl. app flat sucks myself and the cleanest one out there. The double split level just messes up the intake port more.
On the EFI, most want to cheap out on the spacer height and then you end up butchering the lower a lot more in compensation trying to create a plenum to only make manifold in effect flatter, then the outboard ports lose power from the instant sudden turn there with no time to do it. The manifold was designed to be dry not wet and why they turned port hard like that.