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Old 11-14-2012, 11:36 AM   #16405
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Join Date: Mar 2009
Location: Denver, Colorado
Posts: 3,853
My Ride: 2004 SG M3 ESS-550
Originally Posted by Rubenk View Post
Dont side pipes have a sort of scavenging affect at speed? There is a similiar design/idea to the crankcase vent on my deuce, it is routed down by the oil pan so that at speed, the air flowing by helps scavenge.

The main aerodynamic advantage is the fact that hot exhaust gases are a perfect example of the kind of high-pressure air you don't want under the car, the obvious place to put the exhaust outlet is above the splitter or out the side where the gases can't roll under the car. Don't want to place the exhaust outlet right at the tail end of the diffuser, or you risk the high-pressure gases rushing under the car.

So by running the exhaust above the underside of the car not only flattens out the bottom of the car allowing air to move more smoothly but also reduces the amount of pressure creating negative lift.

The way that air passes around the car is less important as how it passes over and under the car.
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