J's racing.

 

weight has nothing to deal with what we are discussing.

 

Nor does this vented rear bumper.....

 

It has everything to do with your statement. CRX's own buttonwillow cuz of their weight advantage.

 

[QUOTE=nichigo,Nov 16 2007, 03:07 PM] It has everything to do with your statement.

 

Not functional, but looks cool for sure If you want help with the let me know

 

Prove it Tommy.

No help needed, I'm a mad man when it comes to working w/ a Dremel.

 

Daaayyum...

 

To promote downforce without drag on a car, you want air to move smoothly (laminar flow) and quickly under and over the car. Essentially, you want to turn your whole car into a wing as much as possible with its bias towards providing downforce rather than lift, i.e. creating high pressure over the car and low pressure under the car. A low pressure region, resulting in downforce, is the result of fast and smooth moving air within a region under the car only a few inches high. Front splitters, undertrays, and rear diffusers help the air move faster and smoother. What the vented/meshed bumper does is it encourages air to move from a small space to a larger space while still under the car. This greatly reduces the speed of the air (think of air passing through a nozzle). In addition, air that goes through a some sort of mesh or screen is only going to result in turbulent flow upon exit. That turbulent flow will create a low pressure region right were you do not want it, immediately behind your car!

Vented bumpers and hoods placed by manufacturers generally serve as a means to promote flow-through of air in order to cool something, usually the engine.

The aero gurus are free to correct the above, but I believe the jist is there. Vented bumpers just ain't aerodynamically functional.

 

All this talk about vented rear bumpers reminds me of that one Simpsons episode...

Homer: [suspicious] Hey, what are all these holes?
Car Salesman: [quickly] These are speed holes. They make the car go faster.
Homer: [sheepishly] Oh, yeeeaaah...speed holes!