Understanding Trail Braking

Trail braking is defined as the combination of braking plus cornering. From the moment you add the first steering input while using the brakes, you are already trail braking. If you're doing a corner and combining braking with steering, you are trail braking. In contrast, coasting means letting the car roll into the corner without any influence of the brakes - literally using 0% brakes. You can be trail braking and then coast for a while (for example, because of a jump) and then return to trail braking.

Why Trail Brake?

Trail braking provides several key benefits:

• It ensures you are using the grip of all four tires by giving more grip to the front tires

• The car is able to rotate more with less steering

• It allows you to brake deeper into the corner, gaining time on entry

• You carry more speed and brake later, gaining time immediately

• It provides a better exit because it helps the car rotate more, enabling you to "point and shoot"

• Trail braking helps rotation happen faster, allowing you to accelerate earlier

In essence, trail braking makes you brake later and accelerate earlier. Without trail braking, you have to brake earlier because the car is going to rotate less. By the time you start turning in, you'll have to wait, and you'll also get back on power at a slightly later phase because the car won't have the best line possible to prepare for the exit.

Why Trail Braking Is Difficult

The secret to successful trail braking is that it will only work if you combine it with the steering. If you start to trail brake but forget the steering, then the trail braking has nothing to amplify. Trail braking is always a multiplier of grip for the front tires. If you're multiplying grip that you're not using, you're multiplying zero - you get nothing.

You have to combine trail braking with steering - a little bit of steering and a little bit of braking. You need to feel the resistance of the force feedback as you trail brake to really feel that the car is pointing. When you find that connection, you can resist maybe a tiny bit more, and that will mean a lot more rotation grip.

Common Problems with Trail Braking

Trail braking might not be working for you because:

• You're carrying too much speed

• You're either under the limit on trail braking because you're not finding the magic combination of force feedback plus braking

• You're way over the limit, getting into ABS or locking, resulting in no rotation

• You're rotating the steering way too much, so when you add trail braking you don't feel the difference because the tires are already overheated and destroyed and understeering

Trail Braking as a Moving Target

Trail braking is difficult because it is a moving target. The ideal trail braking when you start to turn still involves a lot of braking and a tiny bit of steering - there's a magic combination for that specific speed. As you go deeper into the corner, that becomes a different magic combination that will provide the best rotation possible, and this continues to change. The ideal trail braking trace is going down as you get deeper into the corner, while the ideal steering is increasing as you get deeper into the corner. If you keep the steering fixed or keep the trail braking fixed, it won't work.

How Much Should You Trail Brake?

Building Blocks of a Perfect Braking Trace

Start with breaking very hard for deceleration, then transition to low brake pressures during the rotation phase while adding steering. However, if you just add steering while keeping the brakes fixed, you get too much rotation or ABS.

In an oversteer-prone car, if you keep the brakes constant and turn while maintaining the brakes, you'll get oversteer. When you notice oversteer and release the brakes very quickly, you shift the weight back and gain more grip on the rear and less on the front. But if you do this too aggressively, you get understeer because the car now has way too much weight on the rear and the front starts losing grip.

The Learning Process

All drivers start with this pattern - without the sensitivity to do quick adjustments yet. As you improve, you start noticing the oversteer at a more subtle level, earlier into the corner. You'll drop the brakes a little earlier, but not all the way, because if you drop too much you don't stop the car and go too fast. You maintain a little brake pressure because you're carrying too much speed.

After the drop, you'll feel a little less rotation (understeer), but this understeer becomes smaller than before because you're releasing less brake pressure. As the speed decreases and the steering increases, you continue braking a little more. Then you might realize you have oversteer again because you maintained the brakes for too long while adding steering. You release the brakes a little until you get understeer again, and so on.

As you get better, you start realizing oversteer on a very subtle level, much earlier. You release the brakes when you sense slight oversteer, and can sense the understeer earlier as well. You build this alternation between understeer and oversteer, releasing and controlling to maintain neutral steer - the car is not turning too much and not sliding forward, just rotating neutrally.

Relationship Between Car Rotation and Brake Release

You release the brakes according to how much rotation the car is having. If the car is oversteer and wants to rotate a lot, you end up releasing the brakes more and carry less trail braking into the corner, because the car already gives you that rotation. However, this is somewhat dangerous because releasing more brakes means carrying more speed, so you need to verify the car can handle that extra speed. If the car is ultra oversteer, you don't want to completely coast just because it wants to rotate - you still need deceleration. You have to find a sweet spot.

In general, the more rotation the car is capable of offering, the less trail braking you need. Conversely, if the car is very lazy, you try to keep those brakes on longer to keep the car pointing. Of course, all of this must be done without turning the steering too much. If you turn the steering too much, you'll slide forward.

The more oversteer the car has, the more careful you need to be with the steering, and the less trail braking you need deeper into the corner.

Downforce Considerations

Whether the car has a lot of downforce is an important factor. With low downforce, the car will do a more V-shaped line, so the closing spiral is more aggressive, and you need to continue decelerating the car more to get rotation. Generally, low downforce cars are heavier and need the brake to continue keeping the car pointing into the corner.

High downforce cars generally have more rotation and are more agile, so you don't need to carry as much trail braking pressure deep into the corner. They also have a more U-shaped line, closer to a circle, so you don't need as much braking because the line radius is not changing as much as in a low downforce car. This is why you carry much less trail braking pressure in a formula car, for example.

Understanding Brake Pressure Percentages

Brakes are measured between 0% and 100%. In a Porsche (GT car), you brake at a high value and continue braking at a pretty high value into the corner, so there's more area and density in the later phase compared to a formula car. In a formula car, you brake and then go down much more quickly, playing with close to 0% brakes or even coasting before getting back on power.

However, in absolute values, formula cars brake much harder due to more downforce and grip. If you measured the actual braking pressure on the tires at the same scale as the GT car, the formula car brake trace would be much higher. The absolute values of braking in a formula car are much higher because there's more grip. Within that 100% scale, the values are compressed to fit in the graph.

It gives the feeling that formula cars brake less, but the difference is not as big when considering actual braking force. The graphs compress the brakes because we think in percentages - 80% braking in a GT car might be equivalent to 40% braking in a formula car. The amount of braking force in high downforce formula cars at 300 kph is equivalent to braking extremely hard in a GT car.

Connecting Trail Braking to Steering

Initially, it's normal to try releasing the brakes more slowly without connecting it to anything else. People are told to release the brakes slowly, so they do it without relating it to steering, to how much rotation the car has, or to the line. What you want instead is to feel the difference and feel the effects of releasing more slowly.

If you're releasing the brakes without knowing exactly how fast it should be, or without knowing exactly why you're releasing that way (just because people told you to release slowly), you need to feel the difference more and more.

Example: Non-Functional Trail Braking

Consider a student who was releasing the brakes more slowly because he was told to, but wasn't actually connecting it with steering. He starts releasing the brakes slowly, but he's not turning. He turned another battery later, then thinks "I should trail brake" and starts releasing the brakes, but he's not actually benefiting from that slow release. He's just under the limit on a straight line. Then he tries to turn more, and you can see the brakes even increasing a little because he realizes he's going wide. This is the clearest example of non-functional trail braking that is not connected to what is actually happening to the car.

Example: Textbook Driving with a Problem

In another example, a student starts releasing the brakes very slowly while actually increasing the steering as he releases the brakes - textbook driving. The problem was that he wasn't really getting peak rotation there. After he completely dropped the brakes to zero, he started adding more steering without the brakes and getting back on power. He was expecting to gain speed and rotation at the same time, so the trail braking was non-functional. He slowed the car too much, and then found himself adding more steering without the help of the brakes. You need the help of the brakes to turn this car.

Subtle Example: Listening to the Tires

In a more subtle example, pay attention to the tire sounds. Initially, the sound comes from the front tires gripping very well because the driver is turning a little bit and braking a little bit. But as soon as he drops the brakes, the sound disappears - nothing. A fraction of a second later, he turns a lot of the steering in a disconnected way from the brakes, just scrubbing the fronts with steering only without brakes, and the sound returns.

The first source of sound was good - he was trail braking and on the limit. Then he dropped the brakes without adding steering, resulting in no sound because he was under the limit. Then he added steering and got sound from scrubbing the front. The second sound is bad; the first one is good because he was actually on the limit of the tires.

What you want is a continuous sound. As you release the brakes, you're always adding steering. If you release your brakes and continue steering the same, you go from on the limit to under the limit.

Trail Braking in Oversteer Cars

You might wonder: if the car already goes and loses the rear with enough rotation, even without braking, shouldn't you avoid trail braking? If you're turning and already lose the rear with just a lift, trail braking makes it even worse, right? Yes, but that does not mean you should not trail brake in these cars.

When the car is oversteer, you can still trail brake in order to get a more spiral line because the corner might be tighter. If you just lift the throttle and yank the car into the corner, you're going to lose the car on entry. Even when there's plenty of rotation, you still want to trail brake. What you do instead is control how much steering you apply to compensate for the excess rotation.

Hand Position and Force Feedback

By relaxing your hands and controlling the balance of the car through relaxed hand positioning, you can manage oversteer. If you start trail braking but don't relax your hands and keep forcing against the force feedback, you'll spin immediately even with just 5% brakes. However, if you start braking and immediately relax your hands, allowing the force feedback to counteract, you get a little bit of rotation even when your steering is going the other way.

By relaxing your hands and turning with less force (not necessarily less steering - less steering is a consequence), and starting to brake while relaxing your hands immediately, you won't spin the car. You'll still get a little bit of oversteer, but controllable. The reason for trail braking in this case is to decelerate more and do a more spiral, V-shaped line. You need to decelerate more quickly because of the shape of the corner.

If you just drop the brakes and start turning in at the limit of the car, you'll do a spiral that takes way too long until the car stops. Using the brakes even when rotation is excessive allows for a more aggressive spiraling down approach. The spiral has fewer laps because you're spiraling down more quickly using the brakes. But to avoid losing the car while doing this, you have to relax your hands.

Trail braking is useful even in oversteer cars - you just have to steer less and control the steering. If you keep the steering the same and trail brake, you'll spin right away. If the car is understeer, you won't have this problem. You'll just stay on the limit of the steering and try to get as much rotation as possible.

Feeling Weight Transfer

The easiest way to feel weight transfer and how it affects the rotation of the car is by doing very tiny amounts of throttle and brakes. Whenever you want to learn how the pedals really affect the steering and rotation of the car, use very small amounts of throttle and brakes.

If you apply just a little bit of throttle, you can see that speed is still going down but you're not losing the car. With full coasting, you can see yourself losing the car. Getting back on power a tiny bit allows you to regain grip. At these small throttle amounts (2-4%), you're just controlling the balance of the car, not really gaining speed - you're still losing speed.

To really feel the effect of trail braking, 2-4% is already enough to feel the difference. However, remember that you still want to trail brake even in cars that behave this way - you just need to control the steering so you can still benefit from the deceleration and spiraling approach into corners.

If you can feel that you can induce understeer with a very tiny amount of throttle, you're developing the right sensitivity. With tiny throttle amounts, the car won't spin. But without any throttle, it rotates much more.

Maintenance Throttle Technique

If the car is extremely oversteer off throttle or under braking and you cannot handle it because you lose it too easily, you can use a technique called maintenance throttle. This literally means keeping a little bit of throttle. When you start trail braking and get that closing spiral, the throttle keeps the rear tires a little bit loaded, adding more grip to them and allowing you to trail brake more freely and get the speed down without losing the rear so easily.

When and How to Use Maintenance Throttle

This technique should not be overused. If you want to do maintenance throttle because you're losing the car, you should do a tiny bit but not a lot - just enough to help. If you do too much, you're literally asking your car to stop and go at the same time, which is not useful. Use maintenance throttle in very low amounts: 5%, 10%, maximum 15% throttle.

Your number one method of maintaining the car in good neutral steer without spinning should still be relaxing your hands and doing micro corrections on the steering. You should use maintenance throttle if the car is way too oversteer - doing a few corrections here and there in cars that have open differentials (like the Skip Barber, the Ray, the Formula Vee, and other cars with very loose differentials that lose the car easily).

In extreme oversteer situations, you can blip the throttle a little bit to bring the rear back, but you should not overuse this technique because it's less efficient. It's a correction technique, not something you should expect to do all the time. In some specific corners, you may do a blip or two to bring the car while you continue trail braking into the corner.

Important Limitations

Never do maintenance throttle without braking in the entry phase of the corner. If the car is accelerating, you should be spiraling down with maybe a little bit of maintenance throttle as you apply the brakes - overlapping both. But again, just 15% maximum. Try to brake a little and get corrections here and there.

If you look at actual world records, even in these cars, you'll see much less maintenance throttle - you'll barely see any. It's just a blip here or there to correct something aggressive. Ideally, you want to get that rotation and do a few corrections on the steering without using the throttle.

Maintenance throttle is your second tool to correct the car. You can do a little bit of both in case the car is way too oversteer, but it's not recommended to maintain a consistent amount of maintenance throttle because it's less efficient than actually relaxing your hands, communicating with the force feedback, feeling the car turning itself, and controlling it with the brakes and steering first - then throttle (maintenance throttle) a little bit only in extreme cases.

Practice this progression. If you're used to doing way too much maintenance throttle, try to limit it. Relax your hands, let the car flow more and rotate more, and do the corrections by relaxing your hands and communicating with the force feedback.