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      01-14-2013, 07:00 AM   #1
sochermit
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Over/Under Steering

Can someone explain just what is Oversteering and Understeering?
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      01-14-2013, 07:11 AM   #2
b1aze
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Understeer is when the car doesn't turn in as much as you would like it to when coming into and out of turns. The front tires "plow" and you don't get the sharp response you're looking for.

Oversteer is the opposite of that, meaning the rear end comes out more than you want it to.

Both can be adjusted with camber, tires and suspension components. It just want you want the car to do that will determine what to buy and install.
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      01-14-2013, 07:11 AM   #3
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When you go in to a corner and the car doesn't want to turn in but remain going straight...that's understeer.

When you are going around a corner and the back end starts to break loose and come around...that's oversteer.
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      01-14-2013, 07:12 AM   #4
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Not sure if serious?

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      01-14-2013, 07:13 AM   #5
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^hahaha, I saw that episode today...
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      01-14-2013, 08:31 AM   #6
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Recovery from understeer is easy, get off the gas and wait until the tires hook up. You don't even need to totally release the pressure on the gas pedal, just stop trying to go faster, you can't. Once you slow enough for the tires to hook up you will be able to steer and you can try feeding in a little more throttle.

Oversteer is more of a challenge for most of us. You must steer where the rear tires are trying to go while also backing off the throttle a little. When the back end starts to hook up it will want to swing the other direction. You must steer to counteract this until it is following the front wheels again. If you do not do it right, you will swing from side to side until you scrub off enough speed. If you really mess up you will spin.

In both situations, you do not want to make any abrupt movement of anything. Steering wheel and brakes all must be used gently. Your car is trying to go out of control and abrupt movements will help it do that. Your changes must be gentle but not overly cautious. Oversteer is the trickiest by far for me. It is also the most fun to practice.

Safest way to practice outside of a school is a parking lot with snow. Turn of the stability control and try a few. Watch out for light poles.

Jim
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      01-14-2013, 11:04 AM   #7
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Watch any NASCAR race you will see 43 of the best drivers fighting oversteer & under steer. Or maybee they can't turn left without takeing a fellow driver out.
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      01-14-2013, 01:32 PM   #8
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understeer = not in control
oversteer = in control

:-)
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      01-14-2013, 02:08 PM   #9
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in control oversteer = drifting
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      01-14-2013, 02:54 PM   #10
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Some comments....

Quote:
Originally Posted by JimD View Post
Recovery from understeer is easy, get off the gas and wait until the tires hook up. You don't even need to totally release the pressure on the gas pedal, just stop trying to go faster, you can't.
... and/or reduce steering input. Steering less in an understeer situation will help you to turn more.

Quote:
Safest way to practice outside of a school is a parking lot with snow. Turn of the stability control and try a few.
Safest way (asides from Grand Turismo ) is an autocross or other local safety school. Our local BMW club offers both the Tirerack Teen Street Survival school as well as general car control clinics in addition to a full autocross schedule. Both the Teen Street Survival school and the car control clinics usually offer a skid pad where one can safely experience under- and over-steer with an instructor explaining both.

Check your local BMW CCA chapters to see what your club offers.
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      01-14-2013, 02:56 PM   #11
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Quote:
Originally Posted by b1aze View Post
Both can be adjusted with camber, tires and suspension components.
Both are caused by, and can be corrected by driver inputs.
Number one cause for understeer is not camber, tires or suspension, it's too much speed on turn-in . It can be fixed for free
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      01-14-2013, 03:02 PM   #12
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Btw. here's a great explanation from a much older Top Gear:

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      01-14-2013, 04:50 PM   #13
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Quote:
Originally Posted by Tom_135i
Watch any NASCAR race you will see 43 of the best drivers fighting oversteer & under steer. Or maybee they can't turn left without takeing a fellow driver out.
nascar understeer is called a push and oversteer is called loose
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      01-14-2013, 06:06 PM   #14
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Quote:
Originally Posted by int2str View Post
Btw. here's a great explanation from a much older Top Gear:
that is a great video explaination of it. Probably the best i have ever seen.
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      01-14-2013, 11:49 PM   #15
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"If you can see the tree you are about to hit, it is called 'understeering'. If you can only hear and feel it, it was 'oversteering'." - Hans Stuck
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      01-15-2013, 06:28 AM   #16
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Sometimes during oversteer it's best to keep the power going, turn the wheel lightly in the opposite direction that the car is trying to make you spin in and hold it until the car starts to straighten. At this point lightly come off the power while still controllling the steering and the back end should fall back in line. At no point should you turn harshly in any direction, apply mountains of power or come off of the power abruptly; any of those will cause the car to either spin in the direction it wanted to or worse, flip the back end round the other way putting you into a nightmare fishtale where unless your'e lucky you're only a passenger in your own car praying there's nothing to hit.
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