Rear wing on front wheel drive cars

[MIKEY_!]

Was a good one, to bad it didn't work

[langwadt]

In theory, a rear wing will aid a front-wheel drive car in at least two ways. The rear wheels will be capable of greater braking effort at speed. And, with an appropriate adjustment to roll center or stiffness, there will be a bit more cornering ability.

Any additional aero down force is potentially a good thing. But just bolting a wing on is rather useless. A spoiler might well prrovide some of the advantages while actually improving aero drag.

yes, most road cars don't have wings that generate down force, they have spoilers preventing the back end from
generating lift that makes the rear and unstable at speed, remember the first audi TT?

[krisfx]

In what way is the 265 a race only vehicle?

I confess I don't know anything about this car. However, Renault has the impression that it's a race version--

The Mégane Renaultsport 265 Trophy Limited Edition is a race version of the street vehicle, Mégane Renaultsport 250 Cup. To improve its 0-60mph performance, reduction in weight has been achieved by removing equipment, such as climate control (air conditioning remains as standard), tyre pressure monitor, exterior Renaultsport styling, rear armrests, electrically adjustable drivers seat and heated front seats. The reduction in weight has enabled the new limited edition Mégane Renaultsport 265 Trophy to set a new benchmark time for a production-specification front-wheel drive car at the Nürburgring’s infamous Nordschleife circuit. This performance beats the attempts of several far more powerful, rear-wheel drive cars

http://www.gtplanet.net/forum/showthread.php?p=5486898

It is just marketing. Mégane RS 265 is nothing less that a Megane RS with 15HP more, recaro seats and the "Cup Pack" which is avalaible at 1400€ on the RS.

There is a Megane race car, but it look like this:
Removed images

Worth noting the Megane trophy is RWD?

[zonk]

WTCC CRUZE

[Tim.Wright]

I tend to think wings on road cars are a waste of time unless you really have a problem with high speed stability. Otherwise its more weight and drag.

Also putting rear downforce on an already understeering car is only going to add more understeer. The performance limit in terms of lateral acceleration is due to the front axle. That is where you need downforce, not the front.

The touring car is another thing. This would be setup more neutral and would benefit from a rear wing for stability reasons.

Spend the money on tyres.

EDIT: Good choice -

Thanks for the help guys.
i think the benfits are mostly for track cars, not a road car.
i have decided not to get it

instead going for ligter wheels and grippier wider tyres is much more benifitial.
and some better springs would help me with grip

Tim

[marcush.]

for a FWD race car a rear wing does make a lot of sense:

You will inevitably want to have a oversteery car for low to mediumspeed cornering to get rid of the understeer push but as you build speed a oversteery car is completely useless and in effect not very confidence inspireing .A.In high speed corners you need the rear planted so the wing helps to setup the car for quick lower speed cornering mechanically and looks for the slight understeer neutral balance as the speed increases.
This works very well.
If you choose to have a wing or a spoiler -who cares?

[strad]

On a front wheel drive car the rear just wants to swing around back there so anything that glues the back to the ground can't be all bad. That said,,,if you have it set for much downforce you will definately hurt mileage.

[Jersey Tom]

On a front wheel drive car the rear just wants to swing around back there

Oh? Why?

[strad]

Come on Tom...You know way too much to not understand. Disingenuous comes to mind.

[Jersey Tom]

I'm just not following the logic, and can't think of examples where I would associate FWD with significant oversteer or lack of stability.

If by FWD cars we mean consumer, OEM vehicles... those are all designed with a handling spec of light to significant understeer under all maneuvers. (This speaks to Tim's point of adding understeer to understeer).

If by FWD cars we mean FWD racecars (of which there are few) I would associate them with power understeer, sacrificing lateral power of the front as drive torque is applied.

Or do we mean a FWD racecar which has been tuned to have a relatively free cornering balance to make up for the power understeer?

[Tommy Cookers]

not so long ago (certainly in Europe) there were many small, high performance 'hot hatches' that had a lot of rear roll stiffness to help them put their power down in corners and reduce steering 'fight' (manual of course)
this combined with the low rear axle weight and large over-run torque gave these vehicles limit oversteer throttle-off, making them easy to crash (I should know)
Paul Frere (GP & Le Mans winner, MEng graduate, journalist) complained about this in print, eg the best-seller Peugeot 205 GTi

[olefud]

If you choose to have a wing or a spoiler -who cares?

Not much difference, but a Kamm effect spoiler can provide some down force while reducing drag. A wing can vary the AoA to tune down force/drag. With a half spin, a wing will switch to up lift –dicey at speed- while a rear spoiler pretty much kills lift.

[Jersey Tom]

not so long ago (certainly in Europe) there were many small, high performance 'hot hatches' that had a lot of rear roll stiffness to help them put their power down in corners and reduce steering 'fight' (manual of course)

That would be my last point... this was really a thing though? On consumer cars? Seems a bit dangerous! Can't imagine an emergency lane change like that.

[strad]

Early U.S. fwd cars and especially vans were downright dangerous at times Tom. It took a few years..I remember an article in which a Ford guy commented on how much development had gone into the rear of whatever car they were touting, to overcome those handling flaws. It is inherent in the FWD platform imo.

[Tim.Wright]

Paul Frere (GP & Le Mans winner, MEng graduate, journalist) complained about this in print, eg the best-seller Peugeot 205 GTi

I admit, I have been bitten by lift off oversteer in that very car.

Point remains though, a wing would have done precisely F.A. to help the situation. Yes its true there was a lot of development to fix this trait, but it was all suspension and tyre related.