Quote:
Originally Posted by swamp2
This is a concern I raised very early.
The diffuser and meshed part of the rear bumper conver are designed to work in conjuntion with the under body panels of the car. This system, along with the shape of the OEM exhaust canister provide one or more of the following:
- Exhaust cooling
- Differential cooling
- Reduced drag
- Downforce (prob very minor)
Changing the geometry of this area the way many aftermarket exhausts do will certainly change some of the above effects. For the better or worse we won't know but it WILL be differnt than BMW designed and engineered it. |
+1
Exactly! I'm not a physicist or aerodynamicist but based on the fact that I've stayed at many holiday inn express hotels, in the case of aftermarket exhausts with separate canisters and nothing in between, you are actually promoting more differential cooling at the expense of increased rear underbody turbulence from the differential to the valence which increases drag and lift. Very minimal to make a whole lot of difference on a 3700lb car in the course of a lap so I don't think it's anything to worry about.
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