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Ground effect and surface


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#1 mat1

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Posted 12 January 2001 - 19:23

I'm not sure whether this belongs in the Nostalgia-forum or the technical forum. I'll try TNF first.

At the moment I'm reading Lauda's 1984 book The turbo years. In this book he very strongly makes the case against the ground-effect cars of the period shortly before.
As you know the ground effect cars relied on 'sealing' the space under the body of the car with skirts, and had very hard springs, almost no springs at all, to keep the body parallel to the street (and to counter the downforce, of course).
Obviously, this works only on a very smooth surface. Smooth asphalt, no jumps, etc. I think the grond effect cars wouldn't have worked on the Nurburgring for example.
My question is; has in that period ever the idea come up to change the road conditions of the tracks somewhat, in order to make the ground efeect impossible, or at least less effective?

Mat


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#2 oldtimer

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Posted 12 January 2001 - 20:28

Mat, go into a corner of your bedroom and say a 100 times, "Forgive me Max & Bernie, I must not have such thoughts."

Why, whatever will be next? Man hole covers, tramlines, unprotected kerb stones, even cobblestones.

Bad boy, Mat

[p][Edited by oldtimer on 01-12-2001]

#3 mat1

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Posted 13 January 2001 - 13:26

:)

potholes, mmmm.....

But a few jumps would have been sufficient, wouldn't they?

Would the wingcars have performed on the Nurburgring? I'm not sure. I'm not even sure about for example Spa. (I think they never drove there).

Mat

#4 Barry Lake

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Posted 13 January 2001 - 14:33

Originally posted by mat1
...ever the idea come up to change the road conditions of the tracks somewhat, in order to make the ground efeect impossible, or at least less effective?
Mat


I have brought this up many times - but no one listens.

Leaving the bumps and jumps in road circuits would have avoided most of the "sins" of modern race cars.

And what about putting back irregularly-shaped corners and the occasional reverse camber while we are at it?

#5 mat1

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Posted 13 January 2001 - 15:54

Originally posted by Barry Lake


And what about putting back irregularly-shaped corners and the occasional reverse camber while we are at it? [/B]


Exactly, although I'm not sure this would have affected the wing cars very adversely.

Mat

#6 ghinzani

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Posted 18 June 2009 - 02:03

Alternatively has anyone succesfully used ground effects on a road car?

#7 leestohr

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Posted 18 June 2009 - 03:36

I'm fairly certain that most exotic sports cars today have some ground effects, limited by racing standards but still very effective over 150mph. The ground effect at least keeps the tires from lifting off the ground, as was common back in the sixties.
It is not true to assume that bumpy tracks would eliminate the 'sin's of ground effect'. Ground effect cars have very stiff springs, so the car doesn't bottom that much on a bumpy track. You don't have to raise the ride height on a ground effect car nearly as much as a Formula Ford for instance, when arriving at an 'old classic circut'. Now the stiffly sprung ground effect car will get launched into the air occasionally, and it will bottom hard in one or two places on a given track. The good drivers still keep their foot in it, they'll wince at what is happening to the car, but the good one's don't lift. They will try and avoid the worst bumps when not pressed.
I have some experience race engineering at a local track called Pacific Raceways (Seattle Intl. Raceway) near Seattle, actually Kent, Washington. This track hasn't changed much since the early 1970's. All the big names drivers in the '60's and early 70's came here, Dan Gurney, Jim Hall, Brian Redman, Mark Donahue, Unser, etc. The last Pro race was held in the 1980's. Today a little one liter ground effect sports racer turns quicker lap times than anything Bruce and Denny ever did.

#8 AJB

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Posted 18 June 2009 - 06:36

Does anyone remember the Bahamas (?) GP, a Formule Libre "race", reported in the Christmas 1970 issue of Autosport? Part of the track consisted of an open planked bridge which caused the Chaparral 2J serious problems. :)
Alan

Edited by AJB, 18 June 2009 - 18:43.


#9 fines

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Posted 18 June 2009 - 15:12

Would the wingcars have performed on the Nurburgring? I'm not sure. I'm not even sure about for example Spa. (I think they never drove there).

I believe the only year "real" wing cars (with sliding skirts) ran on the Ring was 1979, the F2 Eifelrennen, and most of the teams removed the skirts and readjusted the cars because of the jumps, if I'm not mistaken. Cars with sliding skirts become almost undriveable when those skirts are damaged or even removed accidentally, and with the limited knowledge back then (remember, it was only the third or fourth ever race for those cars, and at Silverstone most of them were almost undriveable even on a billiard table surface!) it was impossible to make the skirts durable enough for the Ring. I'm pretty sure they would have eventually come to grips, but I shudder at the thought of the "learning curve" and the resulting carnage... remember Winkelhock in 1980, with a fixed-skirt car that had just a little nose damage? Took off like a fighter jet! :eek::eek::eek: :down:

Edited by fines, 18 June 2009 - 15:13.


#10 kayemod

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Posted 18 June 2009 - 16:04

Does anyone remember the Bahamas (?) GP, a Formule Libre "race", reported in the Christmas 1970 issue of Autosport? Part of the track consisted of an open planked bridge which caused the Chaparral 2H serious problems. :)
Alan


Sounds like a fictional race for the Christmas issue, someone's idea of a joke, but you mean the Chaparral 2J don't you? The 2H was the least successful Chaparral, chiefly distinguished by a long body, short wheelbase, very narrow track and a huge and rather ugly wing on top. In many respects, the 2H seemed to go against almost everything the Jim Hall had done previously in trying to harness the beneficial effects of downforce.


#11 AJB

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Posted 18 June 2009 - 18:42

Sounds like a fictional race for the Christmas issue, someone's idea of a joke, but you mean the Chaparral 2J don't you? The 2H was the least successful Chaparral, chiefly distinguished by a long body, short wheelbase, very narrow track and a huge and rather ugly wing on top. In many respects, the 2H seemed to go against almost everything the Jim Hall had done previously in trying to harness the beneficial effects of downforce.

Shame on me - of course I meant the 2J sucker car, hence the problems with the open planked bridge. Note the quotation marks around the word "race" in my post, and the Smiley! Hope you don't mind, I've corrected my original.

Edited by AJB, 18 June 2009 - 18:44.


#12 500MACHIII

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Posted 25 August 2009 - 20:08

Alternatively has anyone succesfully used ground effects on a road car?



HI ! As far as I recall the first road car fitted with a sort of ground effect ( eventhough not actually working as it was on F1 cars in 78/80es ) was the Ferrari 355 and for sure the flw 360 Modena which had its bottom shaped so as to get downforce by the air flow between the ground and the car's bottom: as a result higher speed in cornering was claimed.
Possibly a similar aerod. item was there on the Diablo SVR and GTR by Lamborghini.
Honestly,on road cars,even if high perf.sport cars, I dare say that's just marketing..... I have quite a long driving exp. with road sport cars (put aside a single seater stage eons ago) and instead of such gadgets I'd go for better susp.and brake systems overall.
Notwithstanding my cars were not as fast as those I mentioned before,I guess that such items would definately play a minor effect on road use: not the same for true performance susp.systems positively working both at low and higher speeds.
Greetings !
500MACHIII










#13 D-Type

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Posted 25 August 2009 - 20:36

I sometimes wonder about whether other features on road cars are driven by "marketing" - the wing on the Hyundai Coupe, the retactable spoiler on the Porsche [forgotten which model] etc.

Ground effects carried to the extremes that side skirts weren't allowed wouldn't work on a"real" road circuit and the stiff springs would surely exhaust the driver over a race distance (even a modern one).

#14 OfficeLinebacker

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Posted 26 August 2009 - 03:38

All this talk about stiff springs and ride...what about the car where the cockpit was sprung separately from the chassis? That was genius....too bad it was disallowed, the bastards.

#15 Victor_RO

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Posted 26 August 2009 - 07:34

All this talk about stiff springs and ride...what about the car where the cockpit was sprung separately from the chassis? That was genius....too bad it was disallowed, the bastards.


Lotus 88. There was a thread in the Technical section about it.

#16 byrkus

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Posted 26 August 2009 - 08:17

How about combining ground effect with active suspensions...? Still not suitable for jumps, but much more effective (and driver friendly) than ground effect alone, especially on bumpy surfaces.


#17 # 0

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Posted 26 August 2009 - 08:30

....too bad it was disallowed, the bastards.

Why? It was still ground effects, wasn't it? You like cars cornering as if on rails?

#18 f1steveuk

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Posted 26 August 2009 - 10:51

When ground effect was first introduced (Lotus 78) brush skirts were used, until Peter Wright developed first hinged, and finally, along with everyone else, sliding "box" skirts. In this period, the spring rates weren't stiffened that much, that came about with the banning of skirts, the 6cm rule, lowering suspension, and near fixed, solid suspensions. Why do I mention this? Well, in an interview I did with Adrian Newey, he mentioned that even with the introduction of flat bottoms, and the lack of skirts, the difuser could replicate nearly as much downforce by "transmitting the low pressure area to underneath the car" and re-creating ground effect. Active suspension allowed for even better control of this, and even a stall button, that would "spoil" the downforce for the straights, and lower the rear ack down to re-instate it for the corners.

Returning to the original reason for the thread, that would indicate that if tracks were designed to prevent ground effect (in which skirts aren't crucial, see above), designers would have just found a way around it, as ever......

Edited by f1steveuk, 26 August 2009 - 14:50.


#19 barrykm

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Posted 26 August 2009 - 14:41

Does anyone remember the Bahamas (?) GP, a Formule Libre "race", reported in the Christmas 1970 issue of Autosport? Part of the track consisted of an open planked bridge which caused the Chaparral 2J serious problems. :)
Alan


Yes, and didn't a good practice time depend on the timing the tide so that this same bridge was straight? And then wasn't there a local driver with a wooden leg...? :lol:

Perhaps someone could dig it out and post it here?




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#20 f1steveuk

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Posted 26 August 2009 - 14:52

Yes, and didn't a good practice time depend on the timing the tide so that this same bridge was straight? And then wasn't there a local driver with a wooden leg...? :lol:

Perhaps someone could dig it out and post it here? :drunk:


"Post"? "wooden leg" ? Surely not the same bit of timber?

#21 2F-001

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Posted 26 August 2009 - 15:11

As Steve has pointed out, the use of active-ride was a consequence of the banning of venturis (and to a lesser extent sliding skirts before them), Whilst, no doubt, the technology behind active ride could be re-deployed to useful effect on a 'ground-effects' car, I think the two are not essentially complementary.
Re. the Lotus 88 / 88B, whilst the properly-sprung and damped driver and drivetrain were surely a boon to performance and endurance, the real point was that downforce was appilied directly to the wheel uprights where it belonged, making active ride a rather moot point. I believe Lotus were already working on 'active', but put it aside as Plan B - Plan A being the 'twin-chassis'.

The watershed ruling that effectively shaped the development of every winged racing car that followed was surely not the banning of underbody venturi-induced downforce or of the skirts that optimized the effect, but the ruling mid-way through practice at 1969's Monaco GP that banned wings mounted on the unsprung parts of the cars?
What do the front-line designers here think - is that a fair thought, or too much of a generalization?

Edited by 2F-001, 26 August 2009 - 15:11.