Edelbrock perforner rpm vs air gap

I've run both, Air-gap is good for racing conditions where you can keep it consistently cool but in street driving around town it'll get heat soaked which defeats the purpose. Cruising at higher speeds with more throttle will keep the manifold cooler but the gist of it is the tune will never be quite right since the intake temp is always changing. I chose a non-air-gap RPM for my current 360 since it spends the vast majority of its time on the street; it might be down a bit on HP in ideal conditions but at least the tune stays consistent and it's not as temperamental in colder weather. There were times my carb would ice over driving on the freeway in the winter with an Air-gap manifold on a fully warm engine, not fun!

If I was building any kind of 4" stroke SBM it would get a single-plane, hands-down. Heck my 360 is only a "moderate" build (400-450 HP) but I might switch to a single-plane after I swap this 904 with loose 2600-rpm converter and 2.94 gears for a TKX 5-speed and 3.55s.