rear aero??????
#32
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the stock 8 bumper cuts very easily, you could approximate the look of the jdm 9 bumper by cutting away that section.
I have made that cut on my bumper and then placed a ramp I made that directs the air from the underbody to the cut I made on the bumper.
Basically fits to the spare wheel well and then up to the bumper at a height about an inch above the license plate bottom.
#33
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the stock 8 bumper cuts very easily, you could approximate the look of the jdm 9 bumper by cutting away that section.
I have made that cut on my bumper and then placed a ramp I made that directs the air from the underbody to the cut I made on the bumper.
Basically fits to the spare wheel well and then up to the bumper at a height about an inch above the license plate bottom.
I have made that cut on my bumper and then placed a ramp I made that directs the air from the underbody to the cut I made on the bumper.
Basically fits to the spare wheel well and then up to the bumper at a height about an inch above the license plate bottom.
Pics? Or maybe we could meet up sometime and you could show me, I see you are in Bellevue, I'm in Redmond. I know you hit PR I've been meaning to get out sometime this summer.
#34
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To attach it, you basically just want to cut away enough of the bottom of the rear bumper cover that you could lay a yardstick flat against the bottom of the spare wheel well and have it extend out behind the car with no interference from the bumper skin.
You'd want it to sit inside of the bumper something like this:
Here's a really dramatic (and probably inefficient) example of this:
Cutting away part of the bumper, having the diffuser angled upward more, and generally providing a larger rear opening for airflow under the car all should accelerate airflow and reduce drag significantly. That said, all of this extra work over a simple flat plate on the rear isn't going to mean much if you don't address the rest of the underside of the car.
#40
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The diffuser uses sheet aluminum and is bolted into the spare-tire well. The leading edge is not angled upward and probably should be. The other mod I'd add would be to extend the steep section of the diffuser a little bit wider. I originally asked them to extend the diffuser to the end of the gas tank but that would make rear-suspension adjustments a huge pain. For more pics: http://www.norcalevo.net/gallery/thu....php?album=226
I have noticed a slight increase in top speed (especially running Thunderhill backwards into a gusting 40mph headwind. I've also been able to dial out a bit of the APR GTC200 - I compared back-to-back runs at Infineon.
As others have said, diffusers don't contribute much downforce unless the car is *really* low, like 4in or less. However, a diffuser can help reduce drag and help front aero be more effective - front aero is my next plan of attack.
#45
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This is true in SM, not 100% certain in ST, but many of the rules in this case overlap in this area.