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Old 01-31-2015, 06:12 PM   #21
Topless
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Join Date: Nov 2006
Location: Southern ID
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Quote:
Originally Posted by KRAM36 View Post
Can you explain more how the extra drag the spoiler puts on the car actually improves mpg?

Seems I'm not the only person to think about this.

Anyone ever disable their rear spoiler? - Rennlist Discussion Forums

Interestingly in that thread it says the Durametric can disable the spoiler. Will have to dig into this some more, would be nice if it could change the speed settings too. Crud, just realized the person said Durametric Professional and I have the Enthusiast.

Byprodriver even posted in that thread he wished his spoiler raise speed could be changed to 80.
It's a physics thing. By breaking the lift it also partially diffuses the aft vortex behind the car. A major source of drag. The same is true in a standard pickup truck. All the homies drive around with their tailgate down thinking it will improve gas mileage but it has the opposite effect. Having the tailgate in place creates a pressure zone known as a separated bubble that significantly improves the aerodynamics. Both concepts were proven in the wind tunnel.
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Last edited by Topless; 01-31-2015 at 06:18 PM.
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