Engine and Transmission Tech

Quote:
The Performer RPM, with its large plenum, is by far the best 302 manifold, but it will not fit under a stock hood.


How can you make a blanket statement like that without knowing what other components are on the 302?
Example #1 - 302, 9.0:1 CR, Edelbrock E-Street heads, RV type cam and a 500CFM carb.
Example #2 - 302, 12:1 CR, Edelbrock Victor Jr. heads, Comp Cam - 300, Holley 4150 750CFM

Two extremes, I know. One is a very nice street engine that rarely hits 5500RPM, the other doesn't pull until 4000RPM and then pulls hard to 8500RPM. The #7121 is a good manifold when used with compatible components but is not the one of choice for either example. There's more to it than what fits under the hood when picking a manifold.

You're right Jim, there is a lot more to it and believe it or not I do care about performance, but as it's a street car I'm willing to sacrifice a little hp for looks and the clearance. I see that I didn't properly answer the question so let me do it a little better this time. Any other info let me know. 1979 block, Flow-Tek Aluminum heads with 1.94" intake and 1.54" exhaust valves/180 cc intake runner/62 cc exhaust runner/58 cc chambers, Comp 268H cam, Scorpion 1.6 roller rockers, Fast Cars through the fender headers, Professional Products Typhoon intake/4.12" from carb base to bottom of intake which is what I was wanting to reduce but see that's probably not practical, Edelbrock 600 cfm carb, stock pistons, I'm guessing 9.0:1 compression.



Paul

According to the Comp Cams site, the 268 Extreme Energy cam is all done by 5000RPM and loses power above that point so a #2121 (idle - 5500RPM) manifold would be a perfect match for that cam if you wanted something lower than what you have now. Your current manifold, as well as the Performer RPM, are a high rise street/strip design that have a 1500 - 6500 RPM power range which isn't the best match to your cam.

Quote:
The Performer RPM, with its large plenum, is by far the best 302 manifold, but it will not fit under a stock hood.


I've had all 3 on my car - all under the stock hood. The Performer RPM and Performer RPM Air gap required a deep drop base and for me to bend the choke connection tab over but it still functioned. The Performer 289 I now have also works fine. I do use a 2" filter; haven't checked to see if 3" would fit.

Like Jim said, it's the whole package. The dyno test he mentioned did use the 2121, so that cam may have made a bit more power upstairs with a better breathing intake. It was still making good power at 5500 (about 330hp).

Rob, I would be running a 3" filter on my 215 if it fit. You certainly need one.

Update, I sold the comp cam and went with Lunati, a little more RPM on the top and though a little more expensive, I used Lunati in a couple of street rods a few years ago and I like them better than Comp.


Paul