351C Dual Plane?

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wrobinson

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My 13 year old wants to build a 1971-73 Mach 1 Mustang for his first car. We have found a Grabber Blue with white interior base model 1971 Mach 1 to start on.
I have an observation I need some help with. I have been reading a few different articles about intake manifold performance such as the Engine Masters "Ford Cleveland Intake Shootout". The Performer RPM Air Gap really made incredible power, 449hp and 411tq. The 4V 351 responded tremendously well to the smaller intake port. The RPM Air Gap has a port size of 1.42" x 2.04" which is not much bigger than the Eddy Performer 2750 351C 2V intake which has a port size of 1.30" X 1.86". Can the Performer 2750 be used on 4V heads? I have read that the Performer 2665 4V intake is a turd which has a port size of 1.88" X 2.15. Has anyone used a Performer 2750 on 4V heads?

The RPM Air Gap uses a specific gasket, Edelbrock # 7265, which have port sizes of 1.52" X 2.16". I was thinking maybe this gasket could be used for the Performer 2750 also instead of the Felpro # 1240 which has a port size of 1.50" X 2.12".

 
The best all round intake (price and performance) would be the RPM air gap, but if price isn't a consideration, then the Scott Cook dual plane would be the pick. The blue thunder is another great piece, but can be hard to find at times due to availability. Edlebrock deliberately designed the 2665 4V performer port like that for a reason and that being to keep good velocity through out the port, one of the biggest mistakes people make on those intakes (performer and RPM air gap) is port matching them. The 2665 performer is a very decent intake especially for a street car, but if looking to build power beyond 5000-5500 RPM, then either of the other intakes would be the best pick. If Ram Air is on the car then the air gap is out because it won't fit under the Ram Air set up. Nothing wrong at all wrong with the performer as long as it's being used for its designed application, in fact on a true street driving 4V and Max power isn't a consideration, it's the one I strongly recommend. If more than true street driving, than the others are better suited for that purpose. My 73 4V with original 95k miles runs a performer, 750 VS Holley, Pertronix 2 module and coil, Hookers, rollmaster timing set and a Powerbond street balancer, the rest of the engine is as it come from the factory. It's no race car, but it goes damn well for what it is and actually surprises quite a few how well it goes for what it is, but that's it's true application, street car. My new build will running the Scott Cook, but it is a whole different engine design

So decide what you really want out of this engine and then choose an intake to suit the needs your after. Hope this helps out in some way.

Cheers Jason

 
The best all round intake (price and performance) would be the RPM air gap, but if price isn't a consideration, then the Scott Cook dual plane would be the pick. The blue thunder is another great piece, but can be hard to find at times due to availability. Edlebrock deliberately designed the 2665 4V performer port like that for a reason and that being to keep good velocity through out the port, one of the biggest mistakes people make on those intakes (performer and RPM air gap) is port matching them. The 2665 performer is a very decent intake especially for a street car, but if looking to build power beyond 5000-5500 RPM, then either of the other intakes would be the best pick. If Ram Air is on the car then the air gap is out because it won't fit under the Ram Air set up. Nothing wrong at all wrong with the performer as long as it's being used for its designed application, in fact on a true street driving 4V and Max power isn't a consideration, it's the one I strongly recommend. If more than true street driving, than the others are better suited for that purpose. My 73 4V with original 95k miles runs a performer, 750 VS Holley, Pertronix 2 module and coil, Hookers, rollmaster timing set and a Powerbond street balancer, the rest of the engine is as it come from the factory. It's no race car, but it goes damn well for what it is and actually surprises quite a few how well it goes for what it is, but that's it's true application, street car. My new build will running the Scott Cook, but it is a whole different engine design

So decide what you really want out of this engine and then choose an intake to suit the needs your after. Hope this helps out in some way.

Cheers Jason
I really like the Air Gap but have not made up our mind on whether or not Ram Air is a consideration yet. The car will be a restomod daily driver with rare visits to the 1320.

 
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The air gap is a very good intake, but clearance with the Ram Air set up is its only real down fall for our cars. It's one of the reasons I'm going with a Scott Cook dual plane because Ram Air, plus they out perform most other dual planes including the eddy air gap. The biggest plus it looks like a standard intake from the outside. The blue thunder is also high on the list of dual planes for Clevelands. If I was going to high port the heads and fill the floors (not with those stupid looking intake gasket type tongues) with alloy tongues, the CHI air gap dual plane would be the ultimate in dual planes. Unfortunately the do not fit up to the standard 4V port, there was talk of them doing one for the 4V, but nothing has come to light on that subject. But if you're not putting on Ram Air, then the air gap would be the best choice for your build, but do not port match them.

 
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