Wheel well vents

[renault_megane_dci]

My understanding is only front wheel wells can be made to be above car's outside pressure through ducting from the front ....

[Vman455]

Originally Posted by aerohead

I think the Viper has the same Cd as the RAM 1500 pickup,so I don't know how much good the extractor vents did for the car.They're never used in low-drag concept cars,except the 'banana' car.And at Cd 0.201,the 'banana' car is kinda at the high end of low drag.

I also had a Ram SRT-10 at one point (that's where my avatar comes from), and that was listed by Dodge at Cd .45; the 2002 GTS was a claimed .35-.36 or thereabouts if I remember correctly.

Originally Posted by renault_megane_dci

What about the Viper's rear vents ?

Those are the pressure-relief vents from the trunk. Every car has them, usually under plastic panels and venting under the exterior body panel, or in the back of the cab on a truck. I was disappointed they weren't more exotic.

[Vman455]

Aw, shoot--it was the C-class, not the E, with the tail light vents.

[RobertISaar]

Originally Posted by Xist

So, you drive with your window down and you have your engine venting in front of your door?

there is very little about the viper(especially the earliest ones) that is designed for operator comfort, it is a very good example of a car that sets its sights on a single goal(raw, nearly uncontrollable power with everything else in the car being secondary) and doesn't stray from the path very much.

i would never want to own one, but i would certainly not turn down the chance to beat on it for a little while.

[spacemanspif]

Thanks for the replies gents. In the back of my mind I knew the vents were cosmetic but got me wondering none the less. So basically cutting up the front flares of someone's beetle is a bad idea, aerodynamically speaking???

[Smokeduv]

Originally Posted by Vman455

Aw, shoot--it was the C-class, not the E, with the tail light vents.

Great! I was looking for this image or for the concept in general for the bumper holes thread!

The front wheel well vents are in most of the badass sports cars (Ferrari F40, Enzo, McLaren F1 and P1 and even the Bugatti Veyron, which is made with a low Cd in mind to achieve its high speed record) and they have the engine at the middle, not at the front. In normal sports car they are purely cosmetic, as they are sealed. I know these cars are not ideal when talking about Cd, but maybe we can learn something more about their aerodynamics.

[Smokeduv]

Looking a bit I found this info from BMW.

BMW EfficientDynamics : Aerodynamics

It has many things that are well-known here, but the vents on the side caught my attention

[renault_megane_dci]

Actually I had the 4 series from BMW in mind when I got interested in this thread.

[whatmaycome14]

From the BMW website:

4 Series-
"Aerodynamics.
The entire vehicle design is testament to the BMW EfficientDynamics philosophy. The optimised, aerodynamic front apron and undercarriage feature innovative improvements that reduce air resistance and fuel consumption.
The front apron is a prominent design feature that embodies the BMW EfficientDynamics philosophy. The integrated Air Curtain channels air through two vertical air inlets and along the front wheel arches. The accelerated air flow creates a kind of "curtain" on the outer side of the wheels. Then there is the Air Breather, which channel the air flow at the front wheels. These innovative BMW EfficientDynamics technologies reduce turbulence and air resistance, which in turn significantly reduces fuel consumption.

The flat undercarriage cover, which also shields the engine compartment, is an additional detail that greatly improves the car’s aerodynamics. This new trim elements are not only highly advantageous in terms of aerodynamics: they also improve sound insulation and provide greater protection from rust.

The Air Breather is located behind both front wheel arches and is one of the innovations used to optimise the vehicle's aerodynamics. Together with the Air Curtain in the front apron, the Air Breather greatly reduces turbulence and accurately channels the air flow. This decreases air resistance, thereby reducing the vehicle’s fuel consumption and CO2 emissions."

[serialk11r]

I think a lot of supercars have functional wheel vents as well, but you probably need a wind tunnel or else you might be making your aero worse.