Rear wings?

Sitting here bored and got to wondering, is there some particular reason that everyone puts the big wing at the very, very rear rather than the middle of the car?

I realize that for most production cars packaging would be an issue, but many race or kit cars would easily have a wing, say, mounted to the top of the roll bar which should give a more even distribution of down force.

More even? Sure, but the idea is max down force on the driven tires, and for a RWD car that means the further back the greater the lever arm for downforce to work.

The back end has less weight to begin with, and it is the end that you are trying to keep from sliding around. It is also the end with the traction, and the front area creates downforce on most cars, too.

*I don't actually know anything about the topic, but I figured I would take a guess.

Every one knows the answer to this one.....Because they look cooler...

I always assumed it was for the same reason they usually use larger back tires. The need more traction on the rear of the car to stop wheel spin.

Rice y0

Deck spoilers are like Ram Air - pointless below 100 mph.

Oh... and its spelled "wingz" Like "rimz" and "subz".

Yeah, my wrx was way less stable wingless at 100 then it was with the STi wing.

though that wing was very floppy, I considered the prodrive wing supports, before I wound up selling it.

I presumed it was some kind of sporting regulations that limited you to the rear.

But the rear isn't always the lightest, especially on race cars. On a mid engined car with the front end being so much lighter a wing in the middle seems to make more sense plus on top of the roll bar is about as unspoiled air as you'll get and therefore your wing would be more effective.

I saw a Lotus 7 clone once with a deck lid spoiler mounted up top and I thought that made a lot more sense than putting it on the decklid.

From what I have read-You want a car to be able to rotate on low speed corners so you set the suspension up to favor slight rotation on tight corners. You don't want a rotating tail happy car at high speeds so you add a big wing. Best of both worlds!

MrJoshua wrote: From what I have read-You want a car to be able to rotate on low speed corners so you set the suspension up to favor slight rotation on tight corners. You don't want a rotating tail happy car at high speeds so you add a big wing. Best of both worlds!

That makes sense. Don't know if it's true, but it sounds like it could be true.

But what about dirt track cars with that huge wing right over the middle? I'd forgotten all about them.

sprint cars! and looking at it now, it seems like the side wings (what are they called?) are set up for running in a circle in one direction.

yes, sprint cars are NOT set up to go straight. Not only do their wings generate almost as much downforce sideways, bit they tend to run staggered size tyres on the locked rear axle.

Get on the throttle and the larger wheel tries to rotate the rear...

I also do not know about rear wings on race cars.. but on most street cars with factory rear wings, they are more their both stability and for cleaning up the airflow off of the back of the car.

Most cars, by necessity of design, are rather wing like in profile. Aff a small "spoiler" the trailing edge, and it upsets the "smoother" airflow over the top, canceling lift

car floor pans are essentially a large lift surface, the wing at the rear counteracts that effect, changing it from a positive lift to a negative lift, or vacuum (in effect anyhow.)
Its kind of like how a teater totter works, but the center point rotates on air , the wing is there to achieve balance. a center top mounted wing would change the balance point, or possibly create two balance points. and be more difficult to tune (creates more variables and turbulence.) the better set ups use both front and rear spoilers to create enough down force at front and rear to squish the center point down as low as possible at the desired speed. its also why allot of newer high end sports cars have automatically adjustable wings, to account for forces at different velocities.

there's allot more to it, but that's the way I think of it , makes it easier for me to wrap my brain around the concepts.. besides, i always liked see saws..

924guy wrote: car floor pans are essentially a large lift surface, the wing at the rear counteracts that effect, changing it from a positive lift to a negative lift, or vacuum (in effect anyhow.)

Which is why most rear wings aren't that useful until you add a rear diffuser.

Even though the Enzo doesn't have a honkin' big wing on the back, the under body design highlights some good design features:

wow. Its a shame all that is hidden.

wow. Its a shame all that is hidden.

curtis73 wrote: Deck spoilers are like Ram Air - pointless below 100 mph.

Back when I followed Toyota Supras, this was the reason of the giant wing on the MKIV Supra.

70mph put approx 65-70 lbs of downforce

On the Abomination, > 100 MPH = a twitchy rear. (Both of them, smart asses. ) I wound up with a 10" tall rear spoiler which made a BIG improvement at high speeds. I wondered the same thing, about using a smaller spoiler at the rear of the roll bar but unfortunately Solo I and II rules don't allow something like that (air cannot go underneath an aero device).

I read somewhere or other that the sprint car wings are adjustable by the driver, you pump a lever to add angle. This adds downforce which compensates for the loss of rear weight due to the fuel load burning off. A sprint car cockpit must be a damn busy place during a race.

The wing on my Rondo keeps things stable when heading to soccer practice at 150mph.

Then theres this:

pinchvalve wrote: Then theres this:

Doh! Beat me to it.

Jensenman wrote: On the Abomination, > 100 MPH = a twitchy rear. (Both of them, smart asses. ) I wound up with a 10" tall rear spoiler which made a BIG improvement at high speeds. I wondered the same thing, about using a smaller spoiler at the rear of the roll bar but unfortunately Solo I and II rules don't allow something like that (air cannot go underneath an aero device). I read somewhere or other that the sprint car wings are adjustable by the driver, you pump a lever to add angle. This adds downforce which compensates for the loss of rear weight due to the fuel load burning off. A sprint car cockpit must be a damn busy place during a race.

At some of the bigger tracks you can watch them lower it on the straights and raise it for the corners, the same with Super Modifieds

Playing with wings can be really interesting - I saw a 2.5 lap second variation when testing with one at Spring Mountain. The driver didn't know what I was doing to the wing, and the fastest position ended up right about where we thought it would be.

There was a 956 (962?) at the Mitty, and looking underneath was amazing. The entire bottom of the car was a wing.

I changed the factory wing on my Mustang for a Steeda Street Wing just for looks. I was really surprised to feel a big difference in stability above 80mph. I don't know if it's downforce related or because it smooths out the turbulance created by the vertical wall design of the rear end. of the car. Either way, It definitely has an effect when I wasn't expecting one.

The back of the Trooper has a 'reversed wing'. It starts out parallel to the roof then turns about 85 degrees down so that airflow blows water and dirt off of the rear glass at highway speeds, come to think of it my mom's 1972 Chevy station wagon had something similar at the back of the luggage rack. Anyway, it's at such a steep angle I can't help but wonder how much lift it generates at, say, 80MPH.

The part about the Enzo's underbody aeros reminds me of the original GT40. The class would not allow aero devices so Carroll Shelby and crew put the radiator at the front of the car, put the radiator opening at the front, then had the hot air exit through the hood effectively putting the wing inside the front of the car where it wasn't easily visible.