I noticed that that air filters on the 46mm carbs for the 3.0 are shorter that the ones I had on the 40mm carbs on the 2.0. While investigating I also found that the velocity stacks are shorter. What, if anything does this do? should I look into replacing them with taller ones?
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another shot, don't have pic of the other for comparison...
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Full Version: Shorter Velocity Stacks on bigger Carbs?
It all depends on the VE of the motor.
Overall, taller stacks = more low end torque
Shorter = more HP in the higher rev range.
Again...this depends alot on the Volumetric Efficiency of your motor, the cam, the heads, blah blah blah...
So, I would suggest that you dont change them if they came with the motor.
Rich
Overall, taller stacks = more low end torque
Shorter = more HP in the higher rev range.
Again...this depends alot on the Volumetric Efficiency of your motor, the cam, the heads, blah blah blah...
So, I would suggest that you dont change them if they came with the motor.
Rich
I think the shorter stacks and filters were made for 911's with A/C. It may not make much of a difference if you are using them on a street engine.
Others chime in if I have it wrong
Paul
Others chime in if I have it wrong
Paul
Jake Raby did the definitive study on this issue a couple of years ago. Check the archives.
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