Louvered wheel wells on race cars

[some_other_dave]

Originally Posted by SuperTrooper

The Plymouth Superbird had 'em.

My understanding is that those were actually added to the production cars because the race cars, when lowered and then running on the banked turns, would rub the tire against the top of the fender. So they chopped a hole to make a little room, and stuck the "vent" on it, then they had to do the same thing to the production cars so they could use it on the racer.

Not sure if that is actually true, or "urban myth".

-soD

[lunarhighway]

i've heared that story too but i think it was something they tolled about the vents to confuse the competition...since the true function of these things still discussed here today i think they did a pretty good job.

[cfg83]

Sayyad -

Originally Posted by Sayyad

The vents on the Jetta are likely fully functional but they'd be installed to vent hot air from the engine bay, most likely.

I finally saw the Jetta again last week, and you are correct. The wheel well had no interior holes/slots/connections to the louver vents, so it must be for the engine.

CarloSW2

[red91sit]

Originally Posted by lunarhighway

i've heared that story too but i think it was something they tolled about the vents to confuse the competition...since the true function of these things still discussed here today i think they did a pretty good job.

Aero Warriors - The <I>Scoop</I> On The Scoops

This is the most comprehensive explanation of the superbird / daytona's fender vents. I also vaguely remember hearing that these vents were designed to help remove rubber build up on modern racing cars with their ultra soft rubber compounds.

[delta-aero]

Just joined tonight (UK Time). I was doing a bit of research into some new race car programs and came across the 'Louvres/Louvers discussioin.
Long story short, I reckon you are almost bang on the money. I have put louvres into car panels always wtih the open face away from airiflow. The proifile in side view does not detract from the overall CD of the vehicle as the overall profile will do much more to govern drag and aero coefficients.
However there is alway a low pressure 'dam' at the base of windsheilds and all the louvres but the overall airflow goes past that., thus providing an evacuation effect on that area. This can also be effected by the top view profile of the car and curvature. You can see it in a wind tunnel quite effecifvely. Back to the Fender thing, you are correct in saying that eg. in some LeMans prototype cars the louvre sets can run pretty far back along the top fender surface and this does indeed provide relief to high pressure built up in the Fenderwell due to wheel and tire rotation. In fact most good race cars have greater Wheel and tire offset to bring the rotational "disc' out towards the main body airflow and thus dissipate it that way. Other ways are to use reverse NACA ducts to bring any excess back thru the underbody aerodynamics package to cool both engine, exhaust and rear brakes before putting it to full use via the difusser package to give you the downforce required to keep it hopefully 'glued' down!
Hope it make sense.

[godscountry]

Originally Posted by Tango Charlie

Awesome link, cfg83!
That definitely answers my questions.
Now I'm wondering how to implement it on my Vibe...

I doubt it would do anything in a normal car at normal road speeds.If their was any thing beneficial to be had ,the car industry would implement it.I maybe wrong ?

[freebeard]

Speed holes:


Advanced race car practice:


Engine heat:

[kach22i]

UPDATE: 03/04/2018
We don't discuss race car aerodynamics very often, so I'm just updating this old thread.

Hey, this example below does have front wheel vents in the computer animation, we will wait and see if the final version has them.

Formula E
Formula E - Pelican Parts Technical BBS

Next seasons new car shape

Futuristic cladding built around a conventional single seater chassis

[freebeard]

That conforms to my theory of making a free-standing front fender into a plow shape.

The V-tail rear wing is also interesting. Current best practice?

[Vman455]

Originally Posted by red91sit

Aero Warriors - The <I>Scoop</I> On The Scoops

This is the most comprehensive explanation of the superbird / daytona's fender vents. I also vaguely remember hearing that these vents were designed to help remove rubber build up on modern racing cars with their ultra soft rubber compounds.

This is an interesting article. If anyone else reads it, note that the author's speculation about the fender louvers on the (then-current) 1999 Viper (actually, they appeared in 1996 on the GTS and 1996.5 on the RT/10) is incorrect. The plastic wheel well liner above the tire is solid, and those louvers cannot vent wheel well pressure.



However, the prominent side vents were/are open to the engine bay and wheel wells; the back part of the wheel well liner there is a rubber flap (just visible in the photo above), which may have served to alleviate wheel well pressure.