Join Date: Jan 2019
Location: Sedgwick, Kansas
Flade, for the most part, all the base Performer manifolds are close, whether it's Performer 302, 289, or just Performer. The Performer RPM is a different beast, well suited to engines with a few mods like headers, better heads, and a cam. RPM Air Gap is even slightly more performance oriented, but can sometimes cause trouble in very cold environments due to its raised plenum and complete lack of exhaust heating.
Performer RPM and Air Gap are both considered some of the finest dual plane intakes available, comparable to the Weiand Stealth.
Original style Performer manifolds are an excellent choice for engines that keep under 5500. They are common as grains of sand on the beach, due to their low pricing and good performance. One of the first upgrades most guys seek when they want to get rid of their old 2-barrel carb and get a 4V - and for good reason.
The RPM and Air Gap version are good to about 6500, which is where roller hydraulic lifters sign off anyway. Beyond that, you're in the range of solid lifters and single-plane stuff, generally.
Edit: I don't want to sound like I'm disagreeing with GT289, because he's not wrong! The Air Gap and RPM are more expensive, but they're excellent - if you have the room under your hood and in your wallet. The Weiand Stealth is also fantastic.
"No matter what you are, be the best one you can." -Abraham Lincoln
Last edited by Grimbrand; 06-08-2019 at 06:44 PM.