I can't figure out why an intake would have anything to do with reversion???

I've switched from dual to single and could never tell the difference. I'm pretty sure I am running a Dart single on port engine and dual plane on starboard engine right now. I Sold a set of heads and the guy needed a fully ported, raised floor dual plane intake for a mud truck. I pulled one dual plane off of my boat and sold it cause I had 2 darts that I wanted to put on. After noticing no difference I never got around to putting the other Dart on. Both engines run pretty much identical. We need a significant differentiation in power to see a performance difference. I think 10-15hp or TQ here and there might just be the "seat of the pants dyno we might feel".

Reversion is all about the exhaust charge getting sucked back into the engine when the exhaust valve is off its seat while the piston is traveling downward. The downward motion of the piston creates a low pressure area in the cylinder, which is also how the intake charge is pulled into the cylinder. However, if you have sufficient velocity and inertia with the intake charge, it fills the cylinder and alleviates the exhaust wanting to come back into the cylinder to a certain extent. This is another reason that supercharged applications are typically less prone to reversion - the positive pressure from the intake charge does not allow much, if any, exhaust charge to get back into the cylinder. Dual plane manifolds typically produce more velocity with the intake charge at lower RPM's, so an engine equipped with one may be less prone to reversion.

If anyone has a edelbrock 7562 (454 rectangle port) I am in the market and may be interested. Thc

I have a nice one. PM me.