A debate: Downforce=Drag?

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Victor Vance

Victor Vance

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Apparently in GT3 high-downforce cars like the Zonda C12R top out at a lower speed than it's less powerful cousin the C12S. So, I ponder to myself, does downforce=drag? And an incredible top speed be obtained in a low-powered car with zero downforce? My 700-horse super-downforce equipped Mini, which tops out at 160, begs this question.
 
Yes, downforce = drag, in a big way. It's the fundamental compromise F1 designers must face. On a tight course, though, the extra cornering speed is worth the tradeoff in terminal velocity. But on the Test Curse, you will win races more easily by minimizing downforce, since you don't need the cornering ability.

But of course, the car has drag of its own, regardless of downforce, so that low power still has to overcome air resistance. Resistance goes up as the square of velocity, so as you go faster, it takes exponentially more power to go faster still.
 
Indeed...

I've been posting in the "test course speed" thread regarding the Lotus Esprit V8 SE, which can run up to more than 1000 hp.

In all of the runs I did on the test course to break in that car I ended up with laps of 1'30.000 and speeds in excess of 270mph.

That is purely because there is no downforce on the car.
Pays off on the big circle, but on the curvy tracks it would be nicer to have serious downforce.

Oh well. :D
 
Downfore is nothing more than a reverse airplane wing bolted to the car, it directs the air upward and pushes the car down, hence the name "downforce". The more downforce you have the more grip you have in the corners, the trade off of course being more drag on the long straights.
 
And, true to life, additional front downforce has little effect on top speed (well, in GT3 it has no effect at all), but additional rear downforce hampers your progress a little.
 
whats really cool, saw this on discovery channle,


Says that a F1 car can drive on the cielieng and still handle better then a normal car can on the ground while raceing :dopey:
 
At 200mph an F1 car generates around 1500kg of downforce - the car and driver weigh a little under 600kg. If it were possible to do so, an F1 car could drive on the ceiling at 90mph.
 
Famine
At 200mph an F1 car generates around 1500kg of downforce - the car and driver weigh a little under 600kg. If it were possible to do so, an F1 car could drive on the ceiling at 90mph.
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So basicly, that means a track similar to a Hotwheels set is possible to race on in real life? Like, loops and 70 degree banks?
 
ya, the only problem is gettin support for the track, wich would be verry hard, the loop itselfe would be very easy to break thru probably :sick:
 
heero 12
So basicly, that means a track similar to a Hotwheels set is possible to race on in real life? Like, loops and 70 degree banks?
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Actually, yes, it would be possible.

Infact, I think it was something like Modern Marvels on the history channel where they did a show that included F1 tech (could have been another show on discovery or something).

Anyway, in this show they did mention that with the levels of downforce and speed that an F1 car runs at, the car should theoretically be capable of running across the cieling of a tunnel without falling off.

I'm sure they were reffering to a top speed/ max downforce run, but still... :eek:
 
Well, of course the car would fall off the ceiling at the first second it was not creating the proper downforce.

So...

I would think they meant that in the sense that, if the car was at top speed with full downforce... then it would stay on the ceiling.

I have no clue though because it really comes down to math, and I'm not big on math. :lol:
 
Thats amazing! Imagine seeing a car drive past you on the ceiling :dopey: In response to an earlier post, a car with 0 downforce would probably start flying at higher speeds!
 
That brings up another point Iceman, would a car going at 200 MPH with negative downforce lift off the ground? I'm sure that if a car could create more than it's own weight in "upforce" that it would surely lift up, thoughts anyone?
 
Yes, that effect is best demostrated in GTA: Vice City, by putting in the flying cars code and getting up to speed, really fun until you hit the ground. Who else here would like to see an F1 car with negative downforce run at the Nevada Salt Flats? I know I would.
 
heero 12
That brings up another point Iceman, would a car going at 200 MPH with negative downforce lift off the ground? I'm sure that if a car could create more than it's own weight in "upforce" that it would surely lift up, thoughts anyone?
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Anybody remember those flying Benzes from a few years ago?

But yes, a car with "negative downforce" is called an "airplane"...
 
Spinning tires cannot force air behind the car either in large amounts over a wide area or in small amounts in a small area, meaning that the car wouldn't have any means of propulsion in the air. And "negative downforce" is called lift in airplane terms.

But back to the topic, yes, downforce = drag because it redirects air off of a smooth course around the car.
 
I would believe if a car had enough negative downforce, it would probably flip over and crash.
 
^boring :rolleyes:

Watch a Bristol race, I don't see those roadcoursing european dudes rubbin fenders and bumping bumpers every other lap, door to door fighting for position, where tempers flare up and driver's aren't afraid to show their emotions, where the late-summer night is cool but the race 'heats things up', where 43 cars are crammed onto a 0.5 mile bullring-shaped 38* banked short track. That, my friend, is real racing :sly:
 
what shape is a bullring!? '0' < or > O. Either way these guys are focusing more on each other than their driving.

Maybe someone could some day turn a F1 car into a light aircraft. Might be hard to work a prop in, although some small jet engines might give you some air time.
 
You're almost always turning, Bristol is almost a perfect '0' and the turns are nearly as long as the straights.

You're right though, you gotta 'drive your rearview mirror' at Bristol, i.e. see who's on your bumper and where. You need a good spotter, too, to help you get through the mess. Don't forget the dreaded Acordian Effect.
 
have you ever seen 'and they walked away' videos? It shows some brilliant examples of NASCAR crashes.

I've tried watching NASCAR (I I'm British, 'Nuff said), and I have seen some of the BUSCH series, but its a hell of alot of yellow flags and boring laps for one or two crashes.
 
"And they walked away"... heh... did you see Richard Petty's 1992 Daytona 500 wreck? Or Mike Harmon's Bristol wreck? Those were pretty bad. Don't you have Days of Thunder or whatever it's called? (you know, Rockingham [not North Carolina])
 
The only mildly interesting part of Nascar is the crashes, and those can be missed too. The fact is Nascar is basicly the average American sport, and those aren't too interesting, IMHO.
 

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