MR2 is well known for snap oversteer and this fact even turned into a mr2 meme that you can find on the Internet. Let’s find out why it happens and what you can do about it.
What causes snap oversteer?
When driving in a straight line, the vehicle is affected, on the one hand, by the force of gravity and traction, the magnitude of which depends on the power developed by the engine, on the other hand, by the force of wheel friction arising at the points of their contact with the road and the force of resistance created on brake drums or discs when the brake pedal is pressed. As soon as the front wheels are turned, the situation becomes more difficult.
First, there is a lateral force perpendicular to the direction of travel at the tire/road contact points, which causes the vehicle to swerve to the side. Secondly, a centrifugal force comes into play which tries to remove the car from the centre of the curve. If you add gas at this point, the centrifugal force increases dramatically. It kind of pushes the car to the outer roadside and takes it to a larger radius (when turning left) or, even worse, “throws” on the lane of oncoming traffic (when turning right). This can happen if the grip of the wheels on the road is not sufficient. To cope with the car in this situation, you need to loosen the centrifugal force, and you need to know how it works.
The amount of centrifugal force depends primarily on the turning radius: the larger the turning radius, the smaller the force. Hence the first rule: the driver must maximize the turning radius using the full width of the carriageway permitted by the traffic regulations. On the other hand, the centrifugal force changes in proportion to the speed square. \Hence the second rule: before you start turning, you have to reduce your speed sufficiently.
Never brake sharply. This can only provoke skidding, but it will never help if it has already started. Only very light (best of all fractional) braking can improve the traction of the wheels.
What is snap understeer?
As a rule, it occurs when the front wheels of the vehicle slide when the steep turn is overcome at increased speed. The same effect occurs when the vehicle is braked sharply on the turning section of the road. Understeer means that it is impossible to change the car’s trajectory when turning the steering wheel.
In order to prevent skidding, it is necessary to observe the driving mode without exceeding the speed on the sections of the road where the road is governed by warning signs. As accident statistics show, accidents caused by lack of handling or loss of handling are usually caused by speeding on sections of the road where speed limits are set. Particular attention should be paid to the speed of the car on a wet road or when it is icing (ice).
If the vehicle shows low steering response and the car has started to lose control due to a loss of grip on the ground, the driver should either gradually release the accelerator pedal or reduce the braking intensity. When turning, if the highway permits, it is desirable to reduce the angle of rotation of the wheels when entering a curved section of the highway. This may not always solve the problem, but any attempt to get out of a semi-accident is always better than inaction. Keep in mind that reducing speed or braking intensity should be done smoothly. The effect can be reversed if there is a sudden action.
What happens when you oversteer?
The reason for it is the unequal speed of the wheels on the axle, the car will turn to the side with which the wheel rotates at a lower speed, as if bypassing this wheel.
The purpose of oversteer is to keep the vehicle within the road surface and to keep the correct trajectory.
One thing is important to remember – on a slippery road you cannot turn and brake at the same time, because there is a high probability of sliding. It seems simple, but actually even experienced drivers do not always cope with this task.
So, on the turn there was a skid on the rear axle of the car (rear wheels slide on the road, and the centrifugal force carries them to the curb). And it’s the rear wheels that drive us. If now you add torque to the driving wheels (that is, press the accelerator pedal), the situation will only get worse – not only that the rear wheels are slipping, but now also tugging, and grip is lost finally.
At the same time it is impossible to press the brake pedal or throw the gas abruptly – in this case the force of inertia will be added to the centrifugal force, and it will only increase skidding. You should remember the common principle – we have to get rid of the reason that caused the skid. And the centrifugal force brings us in. Well, you can’t get rid of it at all, but you can reduce it by reducing speed. You just need to reduce speed smoothly, slightly reducing fuel supply, while turning the steering wheel towards the skid. Once the car’s handling is restored, complete the turn.