Whether you’re a hardcore track racer or a normal driver, you’ve probably heard understeer and oversteer mentioned before. But what do these terms actually mean?
Put simply, oversteer and understeer are physical reactions that drivers experience when cornering. These behaviors affect different parts of the car. Understeer affects the front wheels, while oversteer affects the rears.
For civilian drivers, understeer and oversteer aren’t going to be very common. That said, a basic understanding won’t go amiss. But when driving on a track, experiencing either one will affect your racing line, potentially slowing down your lap time. However, if you understand these terms and deploy them effectively, you can shave precious seconds off your lap times.
In this article, we’ll do a deep dive into understeer and oversteer, explaining what they are and how they occur. We’ll also investigate how you can use them to your advantage by comparing the pros and cons.
Ready to hit the track? Let’s do it!
Understeer occurs when the front tires won’t turn as sharply as the driver wants, causing the car to drift wide and miss the apex of the corner. This is common in front-wheel drive cars because the front tires are responsible for both cornering and delivering power at the same time. With so much demand, the fronts lose grip and carry the car straight on.
The main cause of understeer, especially on the track, is carrying too much speed into a corner. This is compounded when the driver turns in too aggressively, leading to a tortured squeal from the front wheels as they struggle to cope. The car seems reluctant to turn in and instead wants to slide wide. When experiencing understeer, the instinctual response for most drivers is to turn even harder to try and make the corner. Unfortunately, this does nothing to decrease the car’s momentum. Instead, understeer can be remedied by reducing corner entry speed which lessens the demand on the front tires.
If understeer continues to hamper the car, gently lifting off the throttle or easing onto the brakes can scrub off enough momentum to control the car. With the momentum reduced, the car regains access to more grip and can respond accordingly. A brief pause when turning in can also combat understeer, giving the car a chance to catch up with the driver’s input. For drivers who love to get technical, car setup can also be tweaked to reduce understeer. Softer anti-roll bars or front suspension springs decrease the chances of understeer. Taking some air pressure out of the front tires or using softer rubber can also help.
Professional racing drivers know how to use understeer to their advantage. For some drivers, like two-time Formula World Champion Fernando Alonso, understeer forms an integral part of their driving style. A racecar that is set up for slight understeer has more cornering stability and more predictable handling. However, this comes at a cost to initial responsiveness.
During his Championship runs in 2005 and 2006, Alonso used understeer to great effect with his Renault cars boasting some serious rear grip. Fernando was able to turn in hard and maximize the traction from the fronts as they began to slide. This heated the tires more during the entry phase. When the car’s grip returned at an earlier point in the corner, Alonso could accelerate quicker out of the turn.
Oversteer is the polar opposite of understeer. Instead of the front end sliding, with oversteer it’s the rear of the car that loses grip. This often causes a slide as the rear steps out of line. Oversteer is much more common with rear-wheel drive cars because it’s the rears that are responsible for putting the power down. If not caught and controlled, oversteer can quickly see you facing the wrong way in a gravel trap. Oversteer usually happens when the driver gets on the power too early during a corner, when there is less grip for acceleration.
Placed in a difficult position, the back of the car loses grip and slides. Lifting off too much too soon while taking a corner can also cause “lift-off” oversteer – when the weight balance shifts suddenly towards the front. When oversteer strikes, your natural instinct is to try and correct the slide by turning in the opposite direction or to slow the car down by braking. However, both of these actions will only make the problem worse.
Instead, drivers should mimic the direction of the slide with their steering input. So if the rear is sliding to the right, steer to the right. At the same time, a gentle flexing of the throttle will help control the skid. Keep your eyes ahead, focused on your intended direction for the car. Trying to recover from oversteer demands a bit of patience. Even if the car doesn’t settle immediately, don’t turn away from the skid. The rear tires need time to find the grip again. Aggressively steering into a slide also makes things worse. Moderate application of the steering and throttle is your best bet.
As with understeer, there are benefits to having some oversteer on a racecar. A setup that leans towards oversteer will allow the driver to carry more speed into the entry of a corner at the cost of pure stability. Oversteer can also provide a sharper initial response when cornering but will require minute adjustments during the corner. This is why you see Formula One drivers “sawing” at the wheel during a corner, trying to catch a snap of oversteer before it sends them into the wall. To achieve this setup, Formula One drivers and other racing drivers might stiffen the front springs of the car or move the ballast towards the rear. A lower rear ride height can also encourage oversteer.
Is One Better Than The Other?
So now that we know what understeer and oversteer mean, which is better for driving? Well, that’s not a simple question to answer. Both have their own pros and cons, and each driver will likely prefer one over the other depending on their individual driving style.
Pros of Understeer
Mention understeer to most racing drivers and you’ll probably get a roll of the eyes. But as we’ve seen from double F1 World Champion Fernando Alonso, understeer can be incredibly beneficial when used in the right situation.
At most levels of racing, the main benefit to having understeer is that it gives you much more confidence and trust in the stability of the car while also making the handling more predictable, further increasing the driver’s confidence. Understeer can also be a bit kinder to tire wear than oversteer and helps a lot more on wet tracks.
Cons of Understeer
The benefits of understeer do come with costs though. While your car will be more stable during a corner, you’ll likely have a slower corner entry speed. This can potentially cost you lap time. A car that veers towards understeer will also be less responsive overall.
Pros of Oversteer
Many racing drivers will have a slight preference for oversteer instead of understeer. The main benefit of oversteer is that it provides a much faster driving response, allowing drivers to point the nose of the car exactly where they want it. This generates faster corner entry speeds and allows you to carry that speed through the corner.
For certain driving applications, oversteer is vital. Drift racing is the main example of this, as drivers need the back end to be loose to generate their powerslides. Oversteer can be beneficial for rally drivers as well.
Cons of Oversteer
Unlike understeer, oversteer creates a knife-edge in cornering performance. While the car might be more responsive, it’s also much less stable. This demands more effort from the driver to maintain control. Little changes in steering input will be constant to keep the car facing the right way.
Oversteer also wears out tires quicker because of the increased likelihood of sliding. Most racing cars are rear-wheel drive, relying on the rear wheels to deliver power. If the rear tires lose grip, the driver can’t put the power down effectively. Oversteer is also a nightmare to deal with on a slippery or wet circuit.
Have Fun Out There
Part of the fun of track driving is pushing yourself and your vehicle to the limit. Identifying your own driving preferences in terms of oversteer or understeer can help you find significant gains in lap time or race pace. It might take a bit of trial and error, but deepening the bond between man and machine is more than worth it.
Most road cars for civilian roads are designed with more understeer in mind. This is mainly done for safety, but it can take some of the fun out of driving. But there are no such restrictions on the track. Here, you can safely explore whether you prefer understeer or oversteer without the distractions of normal roads.
Will you be the next master of the understeer driving style like Fernando Alonso? Or will you prefer oversteer like the majority of other racers?