phelan

I can't imagine the increase to the drag coefficient from swapping exhausts to be that bad. It's not like the stock exhaust is tuned to provide laminar flow, and that massive black piece of junk in the back of the exhaust is pretty bad design-wise as well (if Nissan actually wanted a "performance exhaust" they'd smooth the front of the curve to guide air better). Every gap and bump will contribute to the drag coefficient, or in essence increase the turbulence in the area.

Yes, the low-slung cans of the FI may be even worse in terms of causing turbulent air flow. But you're better off worrying about the exterior of the car, which will have more say in the drag coefficient, than what's going on with the exhaust.

If you wanted to have a drag car that absolutely had the best aerodynamics possible, you'd put an entire underbody diffuser that guides the air in a straight flow line from front to back.

Side note regarding the wheels: it's a well known adage that reducing unsprung weight is equivalent to three times its amount in sprung weight. So it's pretty good bang for your buck IMO if you're going the weight loss route.

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凛 ('Rin') - 2009 Nissan 370Z
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