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BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > Tracking, Autocrossing, Dragstrip, Driving Techniques > Snap oversteer following understeer on xi?



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      06-10-2008, 04:58 PM   #23
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      06-10-2008, 07:22 PM   #24
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back home in jersey there are tons of twistys but nothing fun up in rochester
yea sorry man. i went to school in ithaca, i know what you mean. it was hard finding a good back road to drive on
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      06-10-2008, 07:24 PM   #25
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Hey,
I had an autocross this weekend with BMWCCA and I certainly continue to learn. At the end of the day I dropped three seconds off my time and was pretty competitive with the better street tire cars. But something really weird happened to me on one of the runs.

Towards the end of the course there was a big sweeper left turn going into a short chicane left right left followed by a straight. I took it a bit quicker on the sweeper this run so as to allow myself to just hold the throttle on the chicane. So I came into the chicane at a good speed, hit left, right, and then felt a bit of understeer and tried to correct by gently rolling off the throttle and the car jerked side to side and then sent me the OTHER way, tossing me off course...

Was this just some freak occurrence that's never happened to anyone? Am I that bad a driver? That happening really confused me.... I mean, I felt that that run the tires were really biting....I don't know if this was caused by me just not being used to the friction from those tire temps or something? Let me know what you guys think.

Thanks,
Dave

EDIT: Some details: Bridgestone Potenza RE-01R 245/45/17 all around, 37 psi rear, 39 psi front, stock suspension all around (until thursday!!!), 85?F ambient temp, 100 octane race fuel

I'm certainly not a veteran race driver here, but I've been "teaching" myself to drive the xi to the limit, which means changing what I know about driving a RWD platform. One thing I've determined is when you feel a bit of understeer, adding throttle can help with the xi. It's something very intuitive to drivers of front wheel drive cars, but a little wierd for RWD vets. I would assume you had all of the nanny controls deactivated?
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      06-10-2008, 07:42 PM   #26
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Quote:
Originally Posted by TurboFan View Post
I'm certainly not a veteran race driver here, but I've been "teaching" myself to drive the xi to the limit, which means changing what I know about driving a RWD platform. One thing I've determined is when you feel a bit of understeer, adding throttle can help with the xi. It's something very intuitive to drivers of front wheel drive cars, but a little wierd for RWD vets. I would assume you had all of the nanny controls deactivated?
Yes all of the nannys were deactivated, maybe I'll try adding throttle next time. That definitely is very counterintuitive especially since I just got comfortable with driving my car to the level I'm driving it now (pretty high if I may say so myself).
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      06-10-2008, 08:28 PM   #27
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You can use the power to the front to try and pull the car through the understeer. Like many have said, I wasn't in the car either, so it may not be applicable, but it's helped me in the past.
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      06-10-2008, 08:36 PM   #28
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Ok so I'm a Computational Math Major... and I may be a nerd but TurboFan that cheer is hilarious
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      06-11-2008, 05:42 AM   #29
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Glad I coud amuse
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      06-13-2008, 01:58 AM   #30
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yup - in an AWD car adding throttle can be very helpful. in fact any tiime you want to go fast - add throttle. what goof are brakes - they just slow you down!
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