Re: edlebrock air gap manifold
the edelbrock air gap and rpm air gap are dual plane manifolds designed to cover rev ranges from idle thru to 6500rpm depending on which one you use. some poeple confuse the air gap with the victor series of manifold which will cover you from 2500 thru to 9000 depending on vic jr, vic or vic super choices. the dual plane airgap manifolds are a prime choice for street/strip on 351 or stroker motor when used up to 6/6500 rpm in a falcon weight or heavier vehicle and a moderate stall convertor, up to around 3500rpm. if you use higher rpm's, more convertor rpm, 3.7:1 or lower diff gears (depends on tyres) less street use or dont need to depend on optimum low to mid range torque, then the single plane type manifolds will give you better results. it's one of those times you need to be honest with yourself, in most cases, the dual plane chioce will give you a faster street car(even if they do sacrifice some top end HP)(topend hp figures are mostly piontless when talking street/strip cars, it is torque and correct gearing/convertor etc that will give you the fastest accelerating car) due to the fatter and higher torque curve they create. unless you can honestly say that you will constantly launch your car at 3500rpm or higher and always run to 7000rpm before thinking of changing gear, the rpm airgap is the right choice.