Question about Spoilers

Ilpav

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I have some questions regarding spoilers. What do they do? Do they benefit road cars (factory-installed and after-market) by increasing fuel economy?

I know they are used mainly for down force, but are they really needed on road cars?

The reason I'm asking is because I am planning to get an '05 Nissan Altima 3.5 SE, and I want to know if I should get one with the factory-installed spoiler? Will it boost fuel economy or is it just there for looks?

Thanks.
 
With normal cars it's just the looks, unless you want to go on the autobahn and past 200 kph.
 
For the most part they will decrease fuel economy because they create drag.
 
I have some questions regarding spoilers. What do they do? Do they benefit road cars (factory-installed and after-market) by increasing fuel economy?

I know they are used mainly for down force, but are they really needed on road cars?

The reason I'm asking is because I am planning to get an '05 Nissan Altima 3.5 SE, and I want to know if I should get one with the factory-installed spoiler? Will it boost fuel economy or is it just there for looks?

Thanks.

If it's a sedan, all it does is make you look like a tard.

If it's a sports car that needs it, all it does is make you look like a rich tard.

But if it is a racing car and you look like this guy, you should be all set :stig:
 
When the Koenigsegg CCX went around the track, Jeremy daid that it needed a spoiler. But in a TG article that I read, they said that it was all down to the suspension setup etc. I guess that spoilers aren't always neccesary.
 
They are pretty much useless unless you are driving faster than any speedlimit i am aware of.
 
Depends entirely on what its purpose is.

SOme spoilers are there for downforce (Ferrari F40, Porsche 911 GT3), some spoilers are for looks (Toyota Camry, Chevy Camaro).

The interesting part is figuring out where on the scale of "Aesthetic <-> Functional" a given car's spoiler lies.

Chances are it's much closer to the aesthetics side. But that's not always the case. The Pontiac Firebird GTAs of the late 80s had a spoiler that was actually very functional. In fact, that car actually had at one point the lowest drag coefficient of any production car, it may still, but Im not sure. A lot of people actually use them as a platform to set land speed records (in stock-appearing body classes)

This is the car and the wing Im referring to:
angle.jpg


These wings actually worked very well.

Sometimes they work well by accident, sometimes it's intentional, but the fact is that for anyone driving on the road, it really doesn't matter. IF you're going 70 mph it's going to do more to create drag than help you with downforce. Their purpose is generally a lot more to make the car look nice than to be functional.

Remember Jeremy talking about the Caparo T1 handling so poorly at low speeds? Thats because even a car with giant spoilers and ground fx will not make downforce at low speeds. It just will not. Most of us never go anywhere near these speeds where downforce becomes useful.

Regardless, if Iwere the one buying the car, I'd buy the spoiler. To me a car looks naked and silly without one. It just balances out the lines of the car much better in most cases although there are some cars that look godo without them.
 
If it's a sedan, all it does is make you look like a tard.

If it's a sports car that needs it, all it does is make you look like a rich tard.

But if it is a racing car and you look like this guy, you should be all set :stig:

:rolleyes: dude, get a sense of fun, will yeah?

By spoilers do we mean spoilers? or wings? spoilers (or lips) ARE effective at reducing lift thats created by having they air shoot directly downwards after they cars backside (caused by the vacuum at the back of the car), and it can effect stability at even 40mph

The original Lotus Elise is a decent example, the rear spoiler IS NOT for looks, they actually had a pretty bad argument about it, but it was decided that the car was too unsafe at speed without the spoiler, so how big is this lip? not big at all

Elise_50anni.jpg


reducing turbulence can also effect fuel economy, so some wings have been noted to actually do a slight increase on highway fuel mileage, slight, but still existent.

When the Koenigsegg CCX went around the track, Jeremy daid that it needed a spoiler. But in a TG article that I read, they said that it was all down to the suspension setup etc. I guess that spoilers aren't always neccesary.

yes but that spoiler WAS necessary, if it did nothing it wouldn't have decreased the top speed by 10mph, so it obviously does at least prevent lift, which is actually much more important in a road car then producing down-force.


Other examples? The current STis wing is actually effective, and it doesn't even look like much
Subaru_Impreza_WRX_STI_1_big.jpg


We also had a discussion about wings with the old mki MR2s back when i owned them, finally one of the race-car drivers decided to take his off, and the car not only didn't pick up any top-speed, but it became much less stable at 120mph, this spoiler, like the others i've posted, is not big or mean, but it is effective.

Toyota-MR2-MkI-For-Sale-600.jpg


furthermore we had a guy by name of Deno Plumley with actual access to a wind-tunnel, he did some tests on the MR2 and found by placing the wing back he could actually go from preventing lift to producing rear downforce. heres what his mod looks like.

DenoPlumleyturbo17.jpg
 
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It really depends on the car. A wing will hardly have any effect on most sedans because the area where you'd expect it to be is a vacum. That's why wings on DTM cars are placed up high and further back.

http://img166.imageshack.**/img166/6724/dtmsonaxslinedy4.jpg

If you must insist on getting a wing, please keep it tasteful. Avoid the type of wing that teenagers with Hondas buy from eBay (yknow what I'm talking about). Consider getting a subtle lip spoiler instead.
 
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Could you give some more info regarding that, I'd love to see how and why it's effective.

i can't give you subarus words of how it works, only my own. I can however quote Tim Colbeck (VP of Sales) that the car has "an aerodynamic form that produces zero lift front and rear"


If your willing to listen i'm willing to explain.

First off its worth noting almost all production cars produce lift, this happens because whenever you have a declining angle more then 20 degrees (or abouts) you will get some a air that is unable to fill in behind all of the crevices (a.k.a. the tailgate) the difference in air pressure creates a vacuum, now what you have is a critical area right were the air diverges over the tailgate which creates a lift, if its close enough to the cars body (which it will be at speed) then it will create lift. However, if you put a small incline at the trailing edge of the car it usually has the ability to counteract any lift by placing the upwards trust from the vacuum a bit farther back from the car, so that the air isn't reacting to harshly on the cars body.

The inverse of this can be seen with defusers, your essentially filling in the vacuum behind the car with smoothly flowing air in a attempt to remove as much of the upward lifting thrust as possible.
 
If big spoilers would be very functional at higway speeds and below, all cars would have one. But they have not.

Greetings, lip
 
If big spoilers would be very functional at higway speeds and below, all cars would have one. But they have not.

Well, to be fair, would you really want your car that dependant on downforce on the road? Then wind on the highway would add more problems than it already does.

And, also, planes have big wings and they can produce lift after 50kts (on a Cessna) depending on the flaps. So big wings on cars would theoretically do the same thing if they are designed right.

I know the wing on my Subi does work, but it's stock so it should... albeit you only start to feel the effects after 80 or 90mph; well above normal legal highway speeds.

I have always been under the belief that if it comes from the manufacturer of the car, with millions of dollars in R&D and the ability to use a wind tunnel, that the part would provide some effect. (Especially on the Subarus and Evolutions where the wings are a huge part of the design)

Aftermarket wings all depend on application for me, but for the most part I've seen them just as ornaments put on by people who don't know any better. I remember one I saw, it was angled against the flow of air like he was setting flaps for landing (It either produced actual upward lift or massive amounts of drag) on his Nissan Sentra. So, unless you know what you're doing a wing is just ornamental and probably detrimental to performance.
 
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i can't give you subarus words of how it works, only my own. I can however quote Tim Colbeck (VP of Sales) that the car has "an aerodynamic form that produces zero lift front and rear"


If your willing to listen i'm willing to explain.

First off its worth noting almost all production cars produce lift, this happens because whenever you have a declining angle more then 20 degrees (or abouts) you will get some a air that is unable to fill in behind all of the crevices (a.k.a. the tailgate) the difference in air pressure creates a vacuum, now what you have is a critical area right were the air diverges over the tailgate which creates a lift, if its close enough to the cars body (which it will be at speed) then it will create lift. However, if you put a small incline at the trailing edge of the car it usually has the ability to counteract any lift by placing the upwards trust from the vacuum a bit farther back from the car, so that the air isn't reacting to harshly on the cars body.

The inverse of this can be seen with defusers, your essentially filling in the vacuum behind the car with smoothly flowing air in a attempt to remove as much of the upward lifting thrust as possible.

There was an article on newest Evo about german Porsche specialist Manthley. They said the reason not creating a body kit for 997-GT3 was that it's aerodynamic form is so perfect it creates zero lift. 996-GT3 didn't achieve the same so it's easy to believe that huge majority of production cars create some lift.

On that STi, is looks quite a bit that the spoiler is there to remove lift. But does roof spoilers like that give any downforce benefits?
The previous gen-STi (one that had two spoilers, other near the roofline and other big one on top of the trunk) looks that spoilers are there for downforce only.
 
if i am correct, the altima is FF.. do not be daft and get a rear wing for a front wheel drive family sedan. Wings are damn useless in FF road cars!

The stability gains from rear wings are because at high speeds, RWD cars may loose some traction through lift. Downforce generated at high speed from the rear wing essentially pushes the back of the car down onto the wheels, giving back traction.

In a FWD car, a rear wing at high speed would have the effect of lead weights in the boot/trunk, decrease fuel economy, and effectively make it harder for the front wheels to 'pull' the car. Thats if its a functional wing, if its cosmetic, it will just be another resistance to the air flow over the car, creating drag, and again, decreasing fuel economy
 
In a FWD car, a rear wing at high speed would have the effect of lead weights in the boot/trunk, decrease fuel economy, and effectively make it harder for the front wheels to 'pull' the car. Thats if its a functional wing, if its cosmetic, it will just be another resistance to the air flow over the car, creating drag, and again, decreasing fuel economy

But, it could also be there to prevent lift, check Ottobon's post.
 
Spoilers are pretty much reserved for upper sports cars and super cars, race cars are just bad ass, on everything they look stupid.
 
Wings are damn useless in FF road cars!

then why does the BTCC (British Touring Car Championship) and WTCC (World Touring Car Championship) use wings? that's the same principle as a road car.

example: the rear wing on a Cobalt SS/SC. i own one. i'm in a club full of guys who have tried the rear wing delete route. they have seriously NOT recommended not going without a rear wing whether it be the SS/SC's stock rear wing or going with the Cobalt SS 2.4's rear wing since both give off the same amount of downforce. trust me, the rearend of a FWD can and will lose traction at higher speeds if there's nothing back there.
 
Because those are tuned engines, producing around 400-500 horsepower. And even when engines don't produce that amount of power, race cars still need to get around corners a lot faster than a normal road car and without all the paraphenelia, they don't generate enough downforce. If you tried to drive a normal car around a track at the pace those cars go, you wouldn't finish one lap without losing it.

The point of this all is: You don't need a spoiler on a road car, because you're not allowed to drive on the road so fast as to need one.

:rolleyes:
 
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