Controlling and correcting understeer and oversteer
Having previously covered the causes of understeer and oversteer, let’s look at the basics of getting out of such trouble. Firstly, to prevent a loss of traction, especially in cold and/or wet conditions, all actions and inputs need to be smooth, gentle, accurate and well timed.
We know that understeer is a result of the front tyres losing adhesion to the road surface, caused by either excessive acceleration and/or steering, or excessive speed for the steering angle required and available grip. To regain control, it is necessary to first remove (or at least reduce) the cause.
Easing off the throttle (and braking if necessary), when understeer occurs is instinctive and helps restore grip thanks to the reduction in speed and forward weight transfer pressing the front tyres on to the road. Unfortunately, it is also an instinctive reaction to wind on more and more steering lock to try and force the car to turn. This merely exaggerates the problem, though, as increasing the steering input when front end grip is lost merely increases the slip angle, taking the tyres further from the point where they will regain traction.
Therefore, though counter-intuitive, briefly release a little of the steering input at the same time as easing off the throttle. Doing so enables the tyres to regain grip that much sooner, and the car respond to the steering input still applied. This is one of those occasions when less means more.
To correct oversteer, we must again remove the cause. First, though, we need to understand what that cause is; i.e. too much power through the rear tyres overwhelming their grip level, or excessive forward weight transfer entering a bend, the transition leaving the rear tyres with insufficient grip on the road. As the causes are different, so too are the techniques to recover the situation.
There is at least a common theme with the steering. Turning towards the slide assists recovery. In the heat of the moment, however, it is not uncommon for drivers to forget which way to turn, either steering in the wrong direction or simply freezing and not reacting at all; whilst some initially turn in the correct direction to begin with, only to change their mind when the car doesn’t react instantly.
Top Tip: Your hands on the steering wheel should normally follow where your eyes lead, so keep looking in the direction in which you want to go.
Quick hands are needed to apply counter-steering and correct oversteer before the angle of drift becomes too large. React too slowly and it will be a struggle to recover control. With the counter-steering set, allow the vehicle time to respond if on a slippery surface. The time this will take depends on the car, the tyres and the grip level. Beware the common mistake of over-correcting with the steering, as this creates a pendulum effect as weight transfers side-to-side and develops kinetic energy; the secondary skid being all the harder to catch.
The disparity in techniques to re-establish grip from an oversteer slide relates to the throttle. To correct a slide caused by power, release the throttle smoothly to remove the cause. If the angle of drift is really severe, dipping the clutch to disengage all torque from the rear wheels can prevent the car being pushed all the way around in a spin.
In a lift-off oversteer situation, where the lack of rear-end weight is the problem, smooth acceleration transfers weight to where it is needed to restore grip. This is very counter-intuitive, and requires ample space to complete safely.
Where space is limited, or when a slow or inappropriate reaction has allowed oversteer to reach a point of no return and a spin is unavoidable, all that is left to do is immediately dip the clutch (assuming a manual transmission) and brake as hard as you can to a stop.
I hope you will never need these corrective skills in real-world, open road driving, but mistakes can happen and boundaries of grip be exceeded, in which case it’s better to have such safe skills reinforced through muscle memory. We can help you safely explore over-limit handling on Millbrook Proving Ground’s vast Steering Pad, where the High G Cornering Circuit is perfect; especially when deliberately soaked to reduce grip and prevent undue stress to your tyres. Do get in touch to find out more.
Check our new e-book: High Performance Principles, comprising over 50 pages of thought-provoking advice and specific techniques; all designed to make driving your sports car all the more enjoyable and rewarding.