thetankwad
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| posted on 28/4/03 at 12:08 PM |
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-PUB ARGUEMENT- help needed
This seemed like the best forum to post this in.
"Lift-off oversteer". Does this get its name from lifting off the accelerator or from the fact that the rear wheel lifts off when it
happens?
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ned
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| posted on 28/4/03 at 12:22 PM |
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not much help for your arguement really as not definitive fact, though IMO it's when you lift off the throttle and the back end steps out. You
need to keep your foot in to maintain traction.
Many production cars lift wheels when cornering hard on standard springs - they don't oversteer!? (nb may be irrelevant!)
beware, I've got yellow skin
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thetankwad
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| posted on 28/4/03 at 12:39 PM |
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The argument spawned from watching the promo video for the Pug 205GTI. Apparently they were famous for L.O.O. and in every shot, the apex-side rear
wheel is never on the ground. Granted, the term could probably relate to both theories, but I want to be right!
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ned
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| posted on 28/4/03 at 12:54 PM |
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I remember seeing on top gear that 306's and vw corrado's suffer from lifting the back rear apex wheel when cornering hard. A friend of
mine who once travelled in the back of my old saxo assured me that used to lift wheels when driven hard too!
I presume this is because front springs on a road car being too soft/for ride not handling - the front non apex wheel being under more force and nose
diving towards the outside of the corner.
Again, probably irrelevant but something to add...
beware, I've got yellow skin
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ned
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| posted on 28/4/03 at 12:57 PM |
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Irrelevant again, but in karting, using a solid rear axle the inside rear will lift if the hubs are set too far in, amongst karters known as
'crabbing' where the rear end has too much grip and the rear inside lifts to scrub round the corner because there's no diff!....
beware, I've got yellow skin
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thetankwad
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| posted on 28/4/03 at 01:16 PM |
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Also happens in streetcars when they have to (carefully) negotiate a turn using “locker” diffs. Tyre tread suffers greatly. As for
soft springs, what kind of Saxo was it, as torsion bar rear suspension would be another factor, as there is no force to keep the rear wheel on the
ground unlike there would be on leaf spring etc.
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thetankwad
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| posted on 28/4/03 at 01:16 PM |
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Also happens in streetcars when they have to (carefully) negotiate a turn using “locker” diffs. Tyre tread suffers greatly. As for
soft springs, what kind of Saxo was it, as torsion bar rear suspension would be another factor, as there is no force to keep the rear wheel on the
ground unlike there would be on leaf spring etc.
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scutter
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| posted on 28/4/03 at 04:40 PM |
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I thought that I'd chuck in my two pennys.
The term lift off oversteer does come from the fact that you back off the throttle, This transfers the weight to the front of the car causing the
rear to "go light", which in turn starts it to drift. Normally the suddenness of the slide is relevant to how sharply you came off the
throttle.
Sits back and wait for flak
All the best Dan.
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Viper
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| posted on 28/4/03 at 04:48 PM |
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No need for the flack jacket coz you are dead right.
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scutter
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| posted on 28/4/03 at 05:16 PM |
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makes a change
Feeling smug Dan.
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uberf1end
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| posted on 28/4/03 at 07:19 PM |
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Both the pug and the saxo are well known for lift off oversteer. So much so that I have a friend who totalled his 205 1.9 GTI within a week of buying
it, his girl then did exactly the same in a saxo but managed to keep it on the road (unlike my mate who span into a field and narrowly missed a
post).
He's no boy racer either. Actually a fairly skilled driver of 2-stroke karts, he just wasn't expecting it to be so brutal.
As for the lifting of rear wheels, I reckon this is partly down to the relatively high centre of gravity on a hot hatch. With violent weight transfer,
it is quite common to have a wheel off the tarmac. If you have ever caught any hot hatch club racing, it is very common.
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thetankwad
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| posted on 29/4/03 at 12:54 PM |
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Ahh bugger. Oh, well, I'm right every other time...
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GO
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| posted on 29/4/03 at 01:49 PM |
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Scutter, you're definately right there.
It's even more of a problem in mid and especially rear engined cars. If you lift off the throttle mid corner, the weight transfers forwards
leaving the rear end low on grip. If you've got the engine behind you the momentum of the extra mass of the engine decides it wants to carry on
and you find yourself quickly facing the wrong way!!
Not that I've ever done that in my mr2!!
Easy solution, dont lift off, keep your right foot planted and hold on!
PS. That last comment wasn't entirely serious and you shouldn't under any circumstances try it, unless you want to. But don't sue
me.
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ned
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| posted on 29/4/03 at 02:06 PM |
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you mean like this: (oops!) or was he hit by the other car (note tyre marks on the front right corner/bodywork...
beware, I've got yellow skin
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Markis
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| posted on 30/4/03 at 11:09 AM |
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Lift-off oversteer
I;ve got the week off work so just passing time here, I think lift-off oversteer happens more in short wheelbase cars eg 205Gti, I have a 309Gti and
when on a fast corner eg roundabouts I would deliberately lift off and get some tale end action easy to do in the wet and although the 205 &
309Gti use the same suspension setup you can controll the 309 easily due to extra lengh and weight on back end. A 205Gti is twitchy at the back end
but break before the corner select appropriate gear and use accelerator pedal to keep car balanced and the grip is phenominal.
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ned
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| posted on 30/4/03 at 11:15 AM |
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You'll always have more lift off oversteer in a short wheelbased car as the rear wheels have to move less distance (sideways) than a long
wheelbased car to be at a greater angle to the road/front wheels.
Hence longer wheelbase cars are easier to control when oversteering (IMO). Also the balance of the car helps - my turbo diesel (yes i know, what a
beast) 306 is very well balanced if getting a bit ragged/near the edge.
beware, I've got yellow skin
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Markis
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 posted on 30/4/03 at 10:29 PM |
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306d turbo
YES great car, they have a slightly wider track than the old 205, driven a few and loved it.
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PHULL
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| posted on 14/6/04 at 10:59 AM |
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aaa
I remeber when I owned a Cooper S and I wacked on a 24 mm rear swaybay it had a habbit of doing that. Lots of fun
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DickieB
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| posted on 15/6/04 at 08:44 PM |
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Front/rear wheel drive and short/long wheelbase are irrelevant. You can always set the car up for lift off oversteer if you so wish. But
you'll rarely get a good lap time if you do.
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greggors84
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| posted on 19/6/04 at 06:05 PM |
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The car lifting the inside wheel is down to it having a stiff set up and chassis, if you watch the clio cups, they do this a fair bit, you will notice
the car doesnt roll more than normal but the inside wheel is in the air.
If it was softer the wheel would be able to stay in contact with the road.
When the stig was driving the clio 182 on top gear the other week he was managing to get the inside wheel really high!
Me thinks these clios have a good chassis!
So did you win or lose the bet?
Chris
The Magnificent 7!
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