Understeer... eh?

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Morat
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Post Wed Apr 12, 2006 9:14 am

A strange thing on the usual drive to work today... GF wasn't in the car so maybe a little faster than normal. There is a left/right downhill 3rd gear bit which I usually take about half throttle and 3k revs until the corner starts to straighten out and then nail it. Halfway round the left hander (second part) where the road flattens out before going uphill again I had a feeling I'd not felt since driving a FWD car... Understeer!

The nose was definitely sliding wide. I backed off the tiniest amount - sort of "unsqueezed" the throttle a bit - and there was a definite feeling of the front end snapping back in and the steering worked properly again. Well, snap is too strong.. more of a wriggle. Very very odd, I didn't think these cars even knew what understeer was? Could something be broken?
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Widge
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Post Wed Apr 12, 2006 9:32 am

No nothing is broken, you just weren't going fast enough! winkeye
Morat
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Post Wed Apr 12, 2006 9:33 am

hehe, fair enough :)
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E30BeemerLad
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Post Wed Apr 12, 2006 9:35 am

i would just check tyre pressures etc mate.

I noticed not long after i got my e30 that when attempting some cock action on local roundabouts, particularly in the dry that if i was going slowly in second and then gave it a stab on the loud pedal that it would push the front end on for a bit before breaking away at the rear.

just sounds to me like you had the car well planted and there was not enough power to break traction at the rear, so it pushed itself out the corner and the front end lost grip before the rear did.

don't think i'd be too concerned mate, but keep an eye on things i guess.
Rosc0PColtrane
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Post Wed Apr 12, 2006 9:45 am

E30BeemerLad wrote:i would just check tyre pressures etc mate.

I noticed not long after i got my e30 that when attempting some c**k action on local roundabouts, particularly in the dry that if i was going slowly in second and then gave it a stab on the loud pedal that it would push the front end on for a bit before breaking away at the rear.

just sounds to me like you had the car well planted and there was not enough power to break traction at the rear, so it pushed itself out the corner and the front end lost grip before the rear did.

don't think i'd be too concerned mate, but keep an eye on things i guess.
Quite, the slight feeling of understeer lets me know my caris poised for some slidey action. The weight of the car is over the front wheels, a bit more steer and a smidgen of power and the understeer will magically become oversteer!!!
Widge
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Post Wed Apr 12, 2006 9:56 am

Yeah, what Lee said was what I meant. Just keep on top of the tyre pressures fi your trying c*#k action as he so eloquently put it.
Morat
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Post Wed Apr 12, 2006 10:03 am

Interesting, I've had the back out plenty (hard not to!) but never had the car sitting exactly at that point of balance for long enough to notice proper understeer. I live and learn :D
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Widge
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Post Wed Apr 12, 2006 10:07 am

Go in to a round about really slowly and hof it in 2nd gear, then you'll feel the front end sledge. Doesn't happen very often, I avoid it now.
Rosc0PColtrane
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Post Wed Apr 12, 2006 12:36 pm

Widge wrote:Go in to a round about really slowly and hof it in 2nd gear, then you'll feel the front end sledge. Doesn't happen very often, I avoid it now.
Yeah definately. Happened once or twice, not good. Doesn't sledge like an fwd tho.

Generally down to poor weight transfer?
Widge
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Post Wed Apr 12, 2006 12:41 pm

Yeah, cos if youre nervous and come in too quickly to the corner you slam the brakes on which puts all the weight over the front wheel-> oversteer when you reapply the go pedal. Bit of a vicous circle really.
e21Jason
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Post Wed Apr 12, 2006 12:51 pm

Hi

When i got my e30 318is i found the same thing, through me a bit after years of more power than grip in e21's. First time it happened i was totally confused, felt the car lose grip, went to correct it, then thought UNDERSTEER AGGH.

Jason
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Post Wed Apr 12, 2006 12:51 pm

Widge wrote:Yeah, cos if youre nervous and come in too quickly to the corner you slam the brakes on which puts all the weight over the front wheel-> oversteer when you reapply the go pedal. Bit of a vicous circle really.
Weight transfer should have been completed before the corner is entered. Turning and braking each affect traction, so the combination, as you quite rightly say, causes it.
Widge
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Post Wed Apr 12, 2006 12:57 pm

Problem is if you go in to the corner too slowly and then punch through in too high a gear so traction isn't lost at the rear it under steers, quite scarry if it's the first time you've driven a RWD car, as you yhnk what's all the fuss about?
Karan
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Post Wed Apr 12, 2006 6:30 pm

they all understeer..... boot it and clutch kick it