Topic: Which Intake Is Ideal?

[gjdls95]

Ok I just sent my carb off to Cliff for him to bring it back to life and was looking at the intake thinking now is the time to do something since I already have the carb off for a while.  I am looking at going to the RARE manifold and exhaust system and for intake I would like to keep the car as original looking as possible so is there something out there that has better performance but still looks OEM or at least has all of the same connections to all of the emissions stuff or am I better off keeping the stock intake?  Any thoughts?

[brian c]

Rocky Rotella (I believe) did a comparison of intake manifolds for the Pontiac engines. His conclusion....the stock iron intake manifolds were better than the Edelbrock Performer. The only gain the Edelbrock Performer gave you was that its much lighter than the cast iron stocker. Apparently GM knew what they were doing when they designed & refined the intake.

Now if you've woken up your valvetrain and compression you may need to switch to an earlier year intake or one off one of the HO 455's. If I'm recalling correctly those were even comparable with the Performer RPM.

I'm sure Mr. P-body will correct me if I've made a mistake as its been known to happen before

[kjkjkcjkcj]

Well for intakes the stock one flows really well. But I bought a edelbrock performer intake. It is pretty much the exact same performance wise as the stock intake but it's about 40 pounds lighter. This intake was under 200 bucks and will allow you to still use the shaker. That is my reccomendation however they also make a better flowing intake called the edelbrock peformer RPM. This will allow more flow but forces you to bolt the shaker to the hood

[kjkjkcjkcj]

Haha brian you beat me to it

[Rick]

Jim Hand reached the conclusion in his book that the Performer only equaled the stock factory cast manifold.  All other aftermarket intakes tested lost performance.  The results are documented in Jim's book on High Performance Pontiac Engines.

Interestingly enough, not all factory cast intakes are the same.  There are some pre-EGR intakes, where the "webbing" between the runners wasn't also cast, that are about 5-6 pounds lighter than the later EGR intakes.  The later ones have material between the runners that add to the mass and don't allow you to see the valley pan.  So it's possible to save a little weight by using an earlier intake, although you have to work out a solution to the hot air choke used on the 73-up carbs.

[Mr. P-Body]

   The '67-'72 factory intakes are very good. It was Pontiac, not "GM" that developed them.  With significant port work, they become VERY good.

   Performer IS lighter. It performs as well up to about 4,500 RPM, where the factory Q-Jet intake is a bit better up to 5,500.

   The first EGR intakes ('73-'75) had a HUGE EGR provision cast into them, hanging underneath.  They easily weigh 30-40 lbs. more than the others. The later EGR intakes (with the "flat" on the secondary openings)  flow better than the earlier EGR units and are significantly lighter. Still a tad heavier than a non-EGR unit.

   Jim Hand's tests were all done on HIS combination, which may or may not apply to yours. We've read the tests. We were there when Cliff tested Hurricane ("Tomahawk") and LOST speed and ET.  Unfortunately, assumptions were made, "lumping" ALL the open-plenum intakes together.  

   We could "debate" this subject forever. We've (CVMS) found the Torker and Torker II to be FAR better performers than any of the other "open" intakes, and in most larger-displacement applications, better than ANY others.  My point is, there are NO "absolutes". Each one has its "place", though some ARE better than others.  Calling the iron intake Cliff and Jim use "stock" is not really fair, as both have MANY hours of porting in them.

  Suffice it to say, there are several to choose from. Your particular combination is what should determine your choice.

Jim

[gjdls95]

Mr. P-Body thanks for the insight.  I am looking to keep the heads original and the carb original with a rebuild from Cliff and the intake was up to debate and depended on if there was anything that was worth the money without changing much else.