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      06-17-2012, 09:55 AM   #1
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Correcting Spin on Track

I know the saying "during a spin both feet in" but that's really when you're beyond the point of correction. Leading up to that point, I know letting off throttle will help the rears regain traction (and braking is the last thing one should do to correct the turn) but what should I be doing with my hands?

The one time my back side came loose was at Summit, last turn before leading into the straights. It was a right hander, slight decline, late apex. Back side was sliding a little to the left and I was able to correct it. Instructor complimented me on my ability to regain control but honestly the actions were more intuitive from my auto-x days. If you ask me now I can't tell you exactly which way I turned the wheel and how many degrees, etc. But I would like to know consciously what I should be doing.
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      07-03-2012, 11:14 PM   #2
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I think that intuition is most important; you don't have time to think about it much, and having that sense of the mechanics involved is a good sign .

My instructor in a car control course discreetly pulled the handbrake during a throttle-modulated skidpad (going around an oval shape without changing the steering angle, just using throttle to cause oversteer and understeer), which was the most crazy feeling ever as we immediately started to spin, but I was able to catch it because of that instinctive reaction.

The right action in my understanding is to counter-steer, e.g. start unwinding the wheel from the direction you are trying to turn in, to "catch" the rear. The idea is to reduce the lateral force that the rear tires are being demanded to hold, allowing them to fall back from kinetic to static friction. Once the rear is planted again, you can immediately resume the required turn (being mindful of suspension loading, which can cause an over-correction and spin in the other direction if you're hasty).
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      07-04-2012, 03:22 AM   #3
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Skid pan is your answer
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      07-04-2012, 05:24 AM   #4
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Oversteer:
I guess it's pretty clear that you should counter steer. BUT you gonna have to be careful, because when you get the traction back, which happens quickly when you go off the throttle, and you don't correct the steering quickly enough back, you will spin out in the opposite way without much chance to hold it. Our car has a short wheel base which only makes it easier to spin out. It's all about training, therefor I plan to do skid pad training in near future.



Understeer:
You'll have to allow the car to get the traction back by turning the steering wheel back out of the turn (and therefor running wider in the turn) and turn back in again when the traction is regained. If you keep turning into the corner you'll actually make it worse.
If you have enough space you can try to "cure" the understeer my power and trying to put the car into oversteer. This should be first trained in save environment and not be tested on the track with other cars anywhere near you.

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      07-04-2012, 05:28 AM   #5
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Counter steer for controlled oversteer only
Come off the power and let the wheel slide through your hands as the backend snaps back
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      07-04-2012, 04:49 PM   #6
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Three thing I teach in my classrooms regarding spins can be summarized in the following acronym:

C.P.R.

Correct. Pause. Recover. Correcting is the easy part. Most of us are ingrained to "counter steer" to correct the initial spin. It's the second and/or third part of the spin that's counterintuitive. Especially if the spin happens at high speed or you've gone past 30 degrees, it's the part that once the outside rear tire has regained traction the snapping motion of the car spinning back the other way that catches everyone off guard. Therefore, as you counter steer to correct, there'll be a split second of "calmness" before the car will snap back the opposite direction. You must pause for that split second of the countersteer, then REACT and recover from the spin by countering the countersteer.

Of course, the most important part of catching a spin, is PREVENTING ONE. And the best way to do so, is not by driving slow. It's by predicting the movement of the chassis and know an impending spin is likely and unwind the steering wheel just ever so slightly more just before the spin starts.
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      07-04-2012, 08:21 PM   #7
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Good stuff here, thanks Hack!
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