By the time you've reached this point in the course, you are probably going much quicker, and more than that, your corner exits are probably already better. Corner exits are mostly consequence. If you have the car on the right angle, on the right place to accelerate, by the time you get back on power, no matter what you do, even if you're not super aware of what you're doing, it's already going to be faster on exit. You're naturally going to have a better throttle application, but we can go even further and know exactly what to do with the throttle.

Understanding Throttle Telemetry and Power Effects

In this lesson, we're going to dive deep into the throttle telemetry traces, what are the stages of throttle application, what are the effects of power on the car balance, on the speed, and how we can really maximize this to make sure we nail the corner all the way onto the exit curve.

Quick Recap: Throttle and Weight Transfer

Let's do a quick recap. Half throttle, weight is on the back, the car is understeering. If you drop the throttle, the car starts rotating a little bit more, and then more and more as you're losing speed. If we touch the brakes, the car gets even more rotation and spirals down more quickly. So far, we've been talking about the throttle as if it only decreases the rotation. However, we can also use the same tool, the throttle, to gain rotation.

Two Effects of the Throttle

We have two effects of the throttle:

• The first one is when we are under the traction limit of the rear tires, it only shifts weight to the rear tires without adding too much stress.

• But if you add way too much stress, then it actually goes over the limit available, because the torque that is being applied on the rear tires uses up so much of the grip on the rear that the tires stop resisting to the lateral grip. We're using so much to push the car forward that it's not capable of holding the lateral grip anymore. If we just smash the power like that, we get wheelspin.

Understanding the Traction Limit

There's a place where this happens though. If you accelerate very slowly and then get there, you can know more or less when to reach that place. That's a throttle percentage basically. At each speed, there is a throttle percentage that will go over that speed limit. For example, if we're too fast, then 100% is not going to do anything because of that high speed, the power being applied to the tires is not going to be enough to break traction. But if there are lower speed and you add the power, it breaks the rear. There is a limit we're going to call traction limit.

When we're exiting a corner, what do we want? We want to get as close as possible to that traction limit without going over. If you go over, the car gains rotation.

The Two Phases of Throttle Application

If you look at the telemetry trace, you will see that there is a fast application, and then there's a modulation. These are going to be the two phases of the throttle application:

• The initial application

• The modulation

Analyzing Throttle Application in Different Cars

We're going to analyze the throttle application in three types of cars:

• A low powered car

• A medium powered car

• A high powered car

And then we're going to see what are the small factors that affect these two stages, the initial application and the modulation.

Three Options for Throttle Application

Basically, we have three options:

Option 1: Accelerating Too Slowly

The first option is accelerating way too slowly. That causes understeer. You're going to understeer a lot.

Option 2: Quick Application with Modulation (Optimal)

The second option is you get back on power quickly, and then you modulate. In this situation, you go straight to what would be the traction limit. Then you get the car in that neutral sphere on the limit, stressing just enough to keep the car rotating and to keep the rear tires on the limit. From there, you modulate to maintain that state as the car gains speed. Because it's gaining speed, the traction limit is also going up. Also, you're losing rotation. You're rotating a lot more early on, and then it will be pretty much in a straight line already. That's why as we lose rotation, we're able to get more and more acceleration.

Option 3: Accelerating Too Hard

If you want to rotate more the car and gain rotation on power, and you accelerate too hard, then you get wheelspin, which pretty much means going over the limit. So you get less torque out of the car, you get less acceleration, and you lose the rear. So that's bad.

Understanding Understeer Snap Oversteer

If you accelerate too slowly under the limit, what's probably going to happen is what we call understeer snap oversteer. Why is that? Because when you get on power, and you're under the limit, you're not rotating the car as much as the car can do. So because you have understeer, you end up having to compensate, take that rotation and forcing the car more towards the late exit phase, which may cause oversteer, and then you lose the car.

Instead of an opening spiral, what you get with this approach is a little bit of understeer right at the beginning. You get a little bit less rotation. Then by the time you reach the later part of the exit, you realize that you're going wide. So you end up forcing the car in trying to get more rotation there. But at this point, the car is already faster. So you really need to get as much rotation as you can at this early exit phase. We're going to do that by reaching the traction limit by accelerating a little bit more aggressively to continue that rotation that we reached at the MRP. Then as the rotation decreases, the car is already straighter on the exit, and you have a lot more room to actually accelerate more quickly.

If you do accelerate more aggressively like that, and you get the car to point where it's able to point, you're going to be able to modulate your throttle earlier and reach 100% throttle earlier.

The Common Trap

This is a trap to so many people because you want to be careful, right? Because you don't want to spin. But you being careful and accelerating too slowly, and then having to force a lot of rotation on the late exit, this is what will make you spin. This is one of the most common causes of spin. You will spin on late exit because you were too careful with your power application on early exit.

Of course, there are exceptions. If you're driving a bumpy track on a car that's already oversteer on entry, you want to roll that throttle more slowly to regain the grip as you gain speed as well.

Adjusting the Speed of Application

You can also adjust how quickly you get to that traction limit. You can do a very quick application, but you can also build it up a little bit more slowly. By adjusting the speed all the way to the traction limit, you determine more or less how much grip the car is going to have.

If you apply it very quickly, you will get a little bit more stress, tiny bit more stress in the car will rotate a little bit more. If you're getting oversteer and you feel like the car is a little bit floaty on mid-corner, you don't want to stress too much tires, you can actually apply it a little bit more slowly.

In short:

• If you want more rotation, you want to get back on power a little bit aggressively, and then modulate.

• If you want less rotation, then you can apply it a little bit more slowly to the traction limit and then modulate it up.

High-Powered Cars

If you have a high-powered car, say a formula one, then the traction limit is already very low. The traction limit of a formula one looks very different. It's insane because the car has so much power and you can only apply 100% throttle when you're on a straight line at a higher speed already. What you want to do is reach that traction limit early, and you can see it gets very tricky on a formula one car because you can adjust this application and then you have to adjust the modulation all the way up for a long period of time because you are consistently on the traction limit of the car as you get out of the corner.

Low-Powered Cars

If you're driving a low-powered car, then most likely you will be able to accelerate very quickly. Or if the car is very oversteer again, you can adjust slightly because the traction limit is already higher, then you can just adjust the timing of your throttle depending on the balance that you're carrying from the corner.

Short Shifting

Now let's talk about short shifting. Why should we even do it? Short shifting means you get lower RPMs and it's very useful if you have a high powered car that is either getting too much torque that is more difficult to control on a lower gear or that is understeering on exit.

Reason 1: Too Much Torque

The first reason is too much torque. Short shifting just allows you to have more travel, more control with your throttle pedal because if the RPM is high, then it's delivering a lot of torque very easily and it's more difficult to control exactly how much torque you're adding to the rear tires. That is just simple. You short shift because the car is so powerful that even on the higher gear in a lower RPM, the car is still able to stay on the traction limit and it gives you a little bit more room to work with.

Reason 2: Understeer on Exit

The second reason is on higher RPMs, some cars might understeer because of the differential locking the tires together. Some cars will actually rotate a little bit more on lower RPMs compared to having exactly the same torque on a lower gear with a higher RPM. This requires a lot of trial and error but I want you to try it yourself. Try second gear exiting a corner and then the same corner exiting on third. If the car has enough power, you're going to feel that on third gear it might rotate a little bit more. Just a tiny bit more that allows you to focus on pointing and then smashing the power more aggressively on exit.

Elevation and Camber Changes

Don't forget that in elevation changes or camber changes there might be more or less grip that you can use on power. So if you have an exit that has a lot of camber, you can smash the power more aggressively or if the car has a compression on exit, smash the power more aggressively. But if you have a lot less grip on exit then you have to not only relax your hands but also give a little bit less throttle because there is less overall grip to be used.