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Old 07-26-2002, 01:20 AM   #1
Fred Zaplitny
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Default Using a subwoofer port as a velocity stack

This is my intake setup right now.


I need to put a tube into the fender from the PRM inlet so it stays put.

I am going to use this (cut down of course)



I will have the flange in the fenderwell and the 3" tube going right to the PRM. What do you think? Minnimal gain, but better that a straight pipe IMO.

Fred
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Old 07-26-2002, 10:05 AM   #2
Legacy777
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I don't think you'll notice any gains.

The main use for the velocity stack is right in front of the MAF to help speed up the air as it enters the MAF.

But you can give it a shot
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Old 07-26-2002, 11:08 AM   #3
Chris Popovich
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The flaring on the port for the subwoofer is to reduce turbulence. While this is nice and all, the big thing to think of is that the subwoofer port is designed for AC fluid flow -i.e. air rushing both in and out. It'll still work fine for the application, but typically a good subwoofer designer will try to kep the air flow at peak velocity less than say, 12m/s, cetainly less than 20m/s, and a 3" or 4" port really won't do that for any driver capable of pushing a lot of air, much less your engine which sucks quite a bit of air.

Anyway, I don't think using the sub port will offer you any significant advantages, more likely you'll realize greater gains by minimizing bends in the pipe and using the largest diameter tube you can.


Chris
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Old 07-28-2002, 11:44 PM   #4
Fred Zaplitny
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Well like I said, I need a 3" tube at the inlet and I think this will be slightly better than a straight pipe. I do not think I'm on to any magical horsepower gainer here! Besides, I'm getting this pretty cheap.

legacy777,
As a general statement, velocity stacks are there to speed up air going into the intake system using the venturi effect. They have been used for years on carburated cars. They do not have to be right in front of the MAF to be effective.

Fred
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Old 07-29-2002, 03:15 AM   #5
US2JDM
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Quote:
Originally posted by Fred Zaplitny

As a general statement, velocity stacks are there to speed up air going into the intake system using the venturi effect. They have been used for years on carburated cars. They do not have to be right in front of the MAF to be effective.

Fred
very true...the rest of the intake tract after the MAF would pretty much negate any increased flow...the most effective velocity stacks tend to be as close as possible to the intake ports themselves.

-Milan
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