How To Correctly Trail Brake in Assetto Corsa Competizione
As a sim racer, chances are you've heard about trailbraking. But what is it, how can you easily use it, and how can this one technique save you seconds of lap time?
In this guide, I’m going to run through the technique of trail braking. And I’m going to show you how using trail braking in Assetto Corsa Competizione can save you seconds of lap time.
If you are looking to find lap time and improve your driving, this is 100% a technique that you should look to learn. And the great news is, it’s not too hard to start doing!
What is trail braking in ACC
We’re all used to the technique of braking in to a corner, and if you’re anything like me. You have the words from previous track events ringing in your ears of “Brake in a straight line before the corner”.
While this is true, and is absolutely how you should approach a corner, if you start trail braking into corners you can brake later, and stabilise your car better in to a turn.
Ultimately, trail braking is the technique of trailing off the brake pedal, or easing off of it as you start to turn the car in to a corner.
As you approach a corner you will want to brake at full pressure like you normally would. However, rather than lifting off the brake pedal entirely before you turn in to a corner. You would ease off the brake pedal gradually and smoothly while you turn in.
What benefits are there to trail braking
When we start to look deeper at trail braking, we start to realise how beneficial it actually is. There are so many benefits to trail braking when compared to lifting off the brake pedal entirely before turning.
I’ll start out by listing just 5 benefits of trail braking in ACC below.
More front downforce on corner entry
Many of us look at trail braking as simply a way to reduce braking distance in to a corner, myself included when I started out racing both virtually and on real tracks.
However, there are so many more benefits to trail braking which will help you find lap time. And the first, and possibly most crucial benefit to trail braking is the added front downforce you can get from trail braking correctly.
To explain this, first think of how a car behaves when you brake hard. As you apply brake pressure the front of the car dips towards the circuit.
With the front of the car closer to the circuit under braking, at that moment in time you have higher front downforce compared to when you weren’t braking. Of course we can’t use this added downforce when braking at full pressure for turning purposes due to grip limitations, but that doesn’t matter in this example.
As soon as you lift off the brakes entirely the front of the car rises back up, which in turn reduces the ultimate front downforce generated.
If you use a standard braking technique on the entry to a corner it’ll look something like this;
- You brake heavily causing the front of the car to dip.
- As you approach the turn in point, you lift off the brakes entirely causing the front of the car to rapidly rise away from the track.
- You turn in to the corner with the nose of the car raised.
- This will generally cause the car to understeer, as the front of the car has reduced downforce with the nose raised.
On the flip side, if you try turning in to a corner with the brakes still applied too heavily one of two things will happen;
- The car will oversteer due to imbalance in the car. When braking all of the downforce is at the front of the car, causing the rear to feel light.
- Or you’re wheels will lock up as there isn’t enough grip to handle both braking and turning at the same time.
Both of these outcomes will ultimately slow you down and cause you to lose lap time. In the first example above, you will have to slow the car down further to avoid excessive understeer. And in the second example, your car will be unbalanced and hard to drive, or you’ll damage your tyres.
This is where trail braking comes in.
By trail braking you are riding the middle ground of the two approaches. By easing off the brakes while starting to turn, you keep the nose of the car dipped, giving you added downforce while turning.
The added downforce that is generated from trail barking opposed to lifting off entirely allows the front of your car to rotate in to the corner better.
Better stability on corner entry
Following on from my point above, when performed correctly, trail braking allows for a much more stable car during the corner entry.
When trail braking you are making the weight transfer during the braking and turning transition much smoother.
When you don’t trail brake, you will find that as you lift off the brake pedal instantly, the whole balance of your car will shift. The weight will all be at the front when braking hard, then will suddenly shift rearwards when you release the brake.
This can often cause instability as you turn in to a corner, as the weight and balance will be moving as you start to turn in. In turn, this can cause the rear of the car to wobble or step out of line.
You’ll find that this can cause your car to be very difficult to drive, and difficult to predict how it is going to react when you turn in to a corner.
By trail braking you are controlling the weight transfer much better, and you’re allowing the balance to stay much more even though out cornering. As a result, you’ll be able to predict your car’s behaviour much better, allowing you to drive more consistently.
Reduce braking distance in to a corner
Now this next benefit doesn’t always apply to every scenario, however more times than not, trail braking can reduce braking distance.
Because you are carrying your braking in to the corner… And due to the fact that you will have slightly more front downforce allowing you to enter the corner faster, as mentioned in our point above. You have the potential to brake later in to corners, saving you extra lap time.
The reason I said that this doesn’t always apply is that for some corners you will need to adjust when you start to lift off the brakes. To maximise your trail braking technique you need to ride on the balance between too much braking force vs too little.
Depending how much braking force you have applied when you turn will dictate how your car turns in to the corner. If you need your car to rotate better in to a slow corner you can apply slightly more braking pressure for longer to allow the front to rotate.
However, as a compromise you may need to start reducing your brake pressure earlier in your braking zone. Because of this, you may still need to brake at the same point as you normally would to get the car slowed down enough before you start trail braking.
Maintain a higher mid corner speed
Using either of the un-recommended braking techniques that I highlighted above require you to slow your car down more to be able to make the corner entry and hit the apex.
Trail braking allows you to enter the corner faster for two reasons;
- Trail braking allows for a faster entry speed as you will be continuing to decelerate while turning in to the apex.
- The added front downforce generated from trail braking allows the front of your car to turn more, requiring less deceleration to make your car turn.
Focusing on my second point above, the extra front downforce is the element that is crucial to increasing mid corner speed.
The extra downforce means your car will turn quicker in to a corner compared to traditional braking where you will have less front downforce.
The quicker rotation of your car means you don’t have to slow down as much before your car rotates in towards the apex. And by not slowing down as much, you will be carrying higher mid corner speeds.
Driving to your car’s full potential
And my last point leads perfectly on to this final trail braking benefit. Trail braking allows you to drive to your car’s full grip potential.
When you brake in a traditional way; braking before turning. Your car’s grip will be focused on doing one thing at a time.
During the braking process your tyres are entirely focused on deceleration. Then during the turning motion the grip is used to turn your car. However, when turning without trail braking you’re very rarely using your car’s full grip potential.
As mentioned above, when braking traditional your car’s balance will be shifting dramatically as you release the brake pedal. This means the peak grip is moving with your car’s balance. In turn, this can cause understeer or snap oversteer.
While trail braking, you maintain a much better balance, and you are completely in control of your car’s overall balance.
For example, if you are approaching a corner, and trail braking on the entry. If you feel the car start to understeer in, you can very subtly increase the brake pressure to rotate the front of the car faster. And the opposite is also true. You can reduce oversteer by slightly reducing your braking input.
This allows you to drive on the limit of your car much better.
How do I trail brake in ACC
So now we’ve looked at why you should be trail braking, let me run you through the full process of how you trail brake in Assetto Corsa Competizione.
I’ve touched on this a little in my benefits of trail braking segments above, but here is the full process of trail braking. This can be replicated completely in Assetto Corsa Competizione.
Corner Entry – Braking
- Brake at full pressure
- Keep full pressure applied as much as possible without locking any wheels until you want to start turning
Corner Entry – Turning
- Start to lift off the brake pedal gradually
- Start to turn in to the corner when brake pressure is lower than 50%
- Brake pressure should be between 35-50% as you start turning
- Decrease brake pressure to 15-25% mid way towards the apex
- Keep gradually releasing the brake pressure to zero just before the apex
- The amount of brake pressure you need to keep applied varies from corner to corner
- The brakes should be fully released by the time you hit the apex, at which point you should look towards accelerating out of the corner
The process above is a perfect example of trail braking. However as I mentioned the brake pressure amounts, and the timings will need to be adjusted slightly from corner to corner.
The best way to perfect this technique is to follow the above process in to every corner around a track, and feel how the car reacts.
If you are over-braking and slowing down too much, try braking a little later. Getting too much understeer? Try applying more brake pressure later in to the corner.
Where and when to trail brake in Assetto Corsa Competizione
In this segment, I’ll run through where you can use trail braking and I’ll answer the question. Can I trail brake into every corner in ACC?
Ultimately, you can use trail braking on almost every corner at every track to some degree. Of course, you will need to tailor how much you trail brake massively to accommodate the corner you’re attacking.
There may be corners which require very little trail braking. However you can still use the technique to a very small degree, mainly to avoid unsettling the car from a harsh brake lift off.
Hopefully the above guide to trail braking will help you find extra lap time in Assetto Corsa Competizione.
My biggest advice when learning this new technique is to try to feel how the car reacts when trail braking.
Try a few laps using a more standard braking technique, and then a few laps using trail braking. And mentally note the difference. Can you brake later? Does the car react differently when you turn in?
Note these elements down and adjust your approach in the coming laps. By feeling how the car reacts to differing brake pressures, you’ll be much better equipped to trail brake correctly around every corner.