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Old 12-24-2003, 10:17 AM's Avatar is offline Moderator
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That is classic performance for a racing manifold used in off-idle service. When you hit the throttle, vacuum in the manifold drops, charge velocity falls drastically and the gasoline that was being carried as a mist/vapor condenses and falls out of the stream. The usual way of overcoming this is to overkill the accelerator pump and dump in a huge amount of gas to compensate for the bog. Not the best way to do it but it works. Forget gas mileage, there won't be any!! Also sounds like you need a higher stall speed torque converter. If you don't have at least a 2000 get one. Better yet for your rather radical combo, get a 2400. Also, you MUST use vacuum secondary carbs - if you have double pumpers, you simply have WAY too much carburation for the street.

One thing you might consider is to reduce the volume of the tunnel ram, especially if your car is mainly a Sonic Drive-In cruiser. Get some Devcon epoxy putty (the industrial stuff, not the hardware blister-pack tubes) and fill the box so there is only a small volume below each carb plus a small (1") crossover between the two plenums. Look at Chrysler's old cross ram manifold they made in 1960-61. Long runners, two carbs and small plenums on a production, street driven car. Reducing plenum size will vastly improve street-ability and won't affect the top end power that much. The power increase from those manifolds is primarily from the length of the runners. There is no need for the huge plenum volume, other than ease of manufacture.

Here is some reading material on the subject.

Cross Ram maniold for a Chevy

Chrysler Cross Ram

More Chrysler info

More Chrysler info

Ram induction theory
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