Originally Posted by cobalt327
Another vote for the RPM sans air gap. The two make basically identical power if the plenum divider is cut the same on the RPM as it comes on the air gap.
I'm thinking an open spacer will accomplish the same. What they are doing is balancing the air flow pulses - and quite frankly, for day to day low and mid throttle operation that will detract from low end performance, idle and even a bit of gas mileage if my engine is an indicator. Might as well have a Victor type IMHO
Aluminum open spacer - gone now, replaced by a phenolic 4 hole version(but no photo):