I've been thinking about getting a rear diffuser latetly to get some better aerodynamics and highway mpg's. So i thought id you guys to see whats up with 'em.

I know F1 cars use them, coupled with a very low ride height, to create a low pressure area under the car and thus get more down force. From what I understand, the diffusers help move the air under the car out faster, which creates low pressure. I figure if I did the same thing, but kept my stock ride height, I could get the air to go under and leave my car in more organized fashion without creating down force.

Am I wack? And are the shelby diffusers functional or show?

Thanks.

 

No, you clearly understand the concept! The lower the car the more benefit though. Also, the more of the wheel opening you can cover up with the diffuser the better, to create more "slipperyness" and less opportunity for turbulence. It's a valid mod, even the oem unit. Whether it results in measurable and significant mpg benefits ... that's the Q I don't think the community has an answer on yet.

 

It ain't doing squat until you get to high speeds, boys.
And I don't mean 80mph, lol.

 

+1

If you're rollin' along at 120 or better on occasion, then yeah. Otherwise, it sure helps it LOOK like you do.

 

Also, unless you have a full underbody cover and a lot lower ride height it isn't going to do jack. Its for looks only (nothing wrong with that, its a very common design style).