Intake recommendations from the 'guru'
...or senior motorhead.

:
If your engine is to be street driven, stick with a dual plane. If the engine is close to stock, stick to the standard Performer (or equivalent). If the engine has been modified with higher compression, hotter cam, headers, etc, you will probably be better of with the Performer RPM. It is all a matter of intake runner or plenum volume.
If the engine will spend 98+ percent of its time on the street and below 5500rpm, stick with the dual plane design like the Performer. That will give you better throttle response in the low-mid RPM ranges. The higher volume Performer RPM intake is better for slightly higher RPMs, like if you have a better flowing exhaust and higher gears. Leave the open plenum or 'single plane' intake manifolds to the strip. You really won't like what they do to your street (low-mid RPMs) performance and gas mileage.
Me? Beta Cat does just fine (
[email protected]) with a stock 4V dual plane intake and stock exhaust manifolds. It does get a little winded above 5200rpm, so that's my limit and shift point. Alpha Cat had a poorly matched engine, with a single plane (Torker) intake and headers on a relatively low compression over cammed engine that Beta would beat. I have since wised up and put a dual plane on Alpha, and upped the compression, and now it runs great.
What I'm trying to say is you have to match your components to your intended use. Too far in either direction and you're asking for trouble.
If you give me the specifics of your engine/trans/ converter/ exhaust/ rear gear I can be of greater help.