In Reply to: Can someone explain concepts of under/over steer? posted by Garrick on June 25, 2000 at 08:58:03:
In real world terms, understeer is when the car won't turn any sharper, even if you turn the steering wheel more. At some point, the front end may start to grip less even when the steering is turned sharply and the result is the car continues in more of a straight line than a sharp turn. That is understeer.
Oversteer is when the car's rear tires lose grip in a turn while the front tires are still gripping. If the rear end starts to slide out from under you in a turn, that is oversteer.
A funny way to put it is if you smash into the wall with the front of your car, it was understeer. If you back into the wall, it was oversteer. Ok, so its not funny, maybe amusing.
Stock production cars are made to have understeer. The US legal system tends to blame the car manufacturer if the car does a 180 before smashing into a wall while if the car can't turn sharp and crunches head long into the wall, then it is the driver's fault.
Most front engine cars have understeer and kinda have to live with it. Most mid-engine and rear engine cars come from the showroom floor with understeer but can be made to handle more neutrally or even have oversteer with minor adjustments. This adjustmenst can be done like the ones most of us have, thinner tires in the front and wider in the back. '99 M3's come with 225 front 245 back. That means you will first lose in the front due to thinner tire right?
If you check the video you will see how you can control a situation when a car oversteer. In this parking lot I make the rear end break lose and then gain control by easing a little bit off the gas, but don't let go or you will regain grip to fast and will bounce to the other side like the s4 did on PM3 video(you guys that have seen the video of PM3 beating the S4 should know that if the driver of the audi didn't let go the gass he would be fine).
Don't try this with cars and curbs around please. Here is the video: Click here for the video, 5MB