I have seen many diffusers for the past 6 months that I have owned my s2k and have no clue what they are or what there function is. Help anyone? Thanks!

 

A diffuser diffuses light.

http://www.yourdictionary.com/ahd/d/d0217400.html

Our headlights contain diffusers where the turn indicators are.

 

Thats the diffuser I am talking about. The one on the back bumper. Whats it do and does it increase hp or just make it more aerodynamic?

 

its an aerodynamic piece that reduces the vortices and vaccum behind the car (which is drag = bad)

sorta like when you drive behind a semi truck and there's all that turbulence....well that's bad drag, so the diffuser reduces that turbulence

 

I've never seen much discussion or underbody diffusers as an application to reduce drag - it's always been in terms of creating downforce. (Although maybe in a low-drag manner?) Anyway, they work by accelerating the airflow under the car - much like an inverted wing. This low pressure area underneath causes the car to be sucked down towards the pavement, hopefully giving increased grip and hence faster lap times. Check out the rear of a Ferrari 360 when you get a chance - those tunnels on either side are diffusers. You can see the upward curve that creates the wing type effect.

 

It takes far more than some plastic below your bumper. You have to look at the whole underside of the car. Two great examples are the Viper SRT/10 and the Ferrari 360. In both casesm the underside of the car is as smooth as the top. Air is channeled through specific areas to provide cooling to the transaxle (360) or the differential (SRT/10), As the air travels aft, the cross-section is increased to provide a "vacuum" effect. Low sides help keep air from spilling in from the sides of the car. The fins in the diffuser help keep the airflow laminar as it exits so that the bubble behind stays small.

 

Thank you guys, now what kind of diffuser is the best for the s2k?

 

Can some1 please tell me what the best diffuser is? Thanks!

 

I seriously doubt anyone's done testing to determine what the "best" diffuser is. To do it properly, you'd need unfettered access to a track or, better yet, a wind tunnel, and to be able to tell the difference while driving, you'd have to be driving on a track or at extreme speeds.

Buy whichever one you think looks best on your car.

Steve

 

Ideally, you really need a car that was designed for a diffuser. As mentioned above, the diffuser works with the design of the entire undercarriage and sides to produce downforce. I haven't seen any numbers, but I doubt slapping a diffuser on the S would do much by itself.