Trailbraking
Published: February 5, 2013; updated: August 2, 2013
Today we are going to discuss trailbraking. This is an advanced driving technique.
Definition
Trailbraking happens when brakes are applied past the turn in point in a corner. Any braking past the turn in point counts as trailbraking.
Unintentional Trailbraking
Most drivers on the street trailbrake into corners. You can easily see this because their brake lights remain on way into turns.
Street drivers do not realize they are trailbraking. Since they typically take corners extremely slowly, trailbraking tends to not affect much of anything.
Novice drivers on the track can similarly trailbrake without realizing it. Unintentional trailbraking at track speeds is dangerous, because applying the brakes too hard or for too long can result in a spin. For this reason instructors usually stop trailbraking in novice drivers as soon as they see it. The typical wording used for this is "brake in a straight line" or "brake, then turn".
Unaware Trailbraking
Intermediate drivers, especially those closer to advanced level, may be trailbraking a little without associating their actions with the term. What these drivers find, through experience, is that timing turn in to happen just as they are getting off the brakes makes the car turn in better. This, of course, is true and the reason it is true is weight remains on the front tires as they are starting to turn which gives them more lateral traction.
Compared to intermediate drivers who trailbrake a little unconsciously, advanced drivers who trailbrake intentionally are on the brakes longer (typically the brakes are released slower) and as a result are able to carry more speed into turns.
What Trailbraking Does
Trailbraking results in weight transfer toward the front of the car. This loads the front tires more and unloads rear tires. As a result, front tires will have more grip while rear tires will have less grip.
The result of correctly performed trailbraking is that the car is more eager to turn, having more front end grip available. The car also gains an oversteering attitude because the rear tires may lose traction due to being unloaded. Trailbraking is therefore a solution for corner entry understeer - where before the car would tend to understeer off the track, with trailbraking the car would fit into the corner.
Another reason for trailbraking is to continue losing speed while entering a corner. This is typically seen in low speed corners following long straights, the best example perhaps being turn 5 at Summit Point Main. Trailbraking allows carrying straightaway speed for longer time.
Trailbraking can be used to a similar effect in long corners. Rather than slowing down to apex speed by corner entry and maintaining that speed from corner entry to apex, with trailbraking the driver turns in at a higher speed and bleeds the excessive speed between turn in and apex.
Execution
It helps to be able to left foot brake, however left foot braking is not required for trailbraking. When downshifts are involved, trailbraking is normally performed with the right foot. Left foot should be used when a downshift is not needed to minimize the time that the car is coasting while you move your right foot from gas to brake and then back.
Trailbraking is a very gentle application of the brakes. Since normally trailbraking happens after a braking zone, trailbraking is essentially a slow and controlled release of the brake pedal. Being extremely smooth is essential.
While trailbraking the car is turning into a corner. In order to realize the benefits of trailbraking, the grip made available as a result of weight transfer accomplished by trailbraking must exceed the amount of grip used to decelerate the car due to brakes being applied. Provided the car is already cornering at close to its absolute potential, the extra grip is not a particularly huge quantity.
Trailbraking And Driver Experience Level
Trailbraking is a perfect example of a driving technique that is initially eliminated from a driver's habits but can, later, return.
Street drivers often trailbrake unconsciously, and do it wrong. Luckily at the speeds they are going, this does not usually create problems. Novice track drivers are instructed to brake in a straight line, eliminating trailbraking entirely. At high intermediate level drivers can start trailbraking again, this time with an understanding of what exactly it is and how it affects the car's handling. Because of this understanding, trailbraking can be performed in a safe manner.
What can you take away from this fact?
- Not everything that is being taught to novice drivers is an absolute fact or rule. Some things are stepping stones meant to be revisited once the driver has more experience.
- As you expand and improve your track driving skills, remember that things you know and do may not be the ultimate way of getting around a race track. Seek advice from more experienced drivers and if they tell you something that contradicts what you were taught in a classroom, it may be because they are assuming a higher driver skill level than the classroom did.
- Novice drivers are not taught how to go around the track in the fastest way possible. If you know everything that novice drivers are taught, you are far from knowing everything.
- A corollary to the previous point is your instructor in novice or intermediate group may run out of things to say not because you know everything, but because you need more experience to arrive at a level where the more advanced driving techniques will be appropriate to bring up.
Tagged: weight transfer, advanced, braking