When discussing racing with fellow motor enthusiasts, you will come across a curious expression that will get your grey matter going — “Brake Boosting.” What does this word mean? Is it simply how it sounds, a boost to the power of a car’s braking? Or is it something seemingly contradictory, like braking the car but then going faster?
The answer may surprise you. Today’s blog is focused on providing you with everything you ever wanted to know about brake boosting but were afraid to ask.
What is Brake Boosting a Car? How Does it Work?
Brake boosting refers to the practice in racing (or launching a car ) where drivers apply the brake and the accelerator at the same time. In doing so, they slow the car momentarily while maintaining enough engine speed and power to “boost” the car, launching it forward once the brake is released. Typically this will only work on cars modified for racing because the fundamental step to creating this effect is preventing the ECU from closing the throttle as soon as you apply the brakes.
Can You Brake Boost While Rolling?
Yes, in fact this is exactly how many drivers achieve this effect, while roll racing. The goal of a brake boost is to maintain sufficient rolling speed before you release the brake and then launch yourself back at greater speed, often to overtake an opponent ahead of you.
It seems an odd concept to use the brakes in order to gain a boost in speed, but when applied properly, the technique can be applied with tremendous effect.
Can you Use Brake Boosting to Launch a Car?
Yes, in a similar guise to features on other cars like BMW’s “Launch Control,” brake boosting can be used to launch from a standstill, but this practice can put a lot of additional strain on the car’s drivetrain, which is why most people who use the technique actually perform a brake boosting manoeuvre from a roll.
Launch control features in cars are designed to use the same principle but can be performed from a standstill. The built-in Launch Control mode of a car like the BMW M4, for instance, is designed to perform this action without putting unnecessary strain on the drivetrain.
Difference Between Brake Boosting and Anti Lag
While the effect of these two actions is much the same, the difference falls in how it is achieved. Rolling anti lag is a function built into the car which when activated — usually by a push-button activation — will limit your vehicle’s speed or engine RPM but not inhibiting your car’s turbocharger. In this way, the turbocharger builds power while the engine is limited to whatever you’ve pre-set in either mph or rpm beforehand.
Brake boosting, on the other hand, is the more direct physical action of applying both the gas pedal and the brake pedal simultaneously and using the gas pedal to maintain and build that same boost.
Is Brake Boosting Bad for Your Car?
The answer is yes, it can be bad for a car. Brake boosting can add a lot of wear and tear to the drivetrain, especially the braking system. If overused, the heat generated can even cause the brakes to smoke and catch fire, which obviously makes the situation a lot more dangerous for all concerned. Some claim that the strain put on the system is only similar to driving the car up a steep hill.
Having said this, it’s not exactly worse for your car than any other racing habit. Don’t forget that when you are racing a car, you are pushing it to the very physical limits of its mechanical abilities. Brake boosting is bad for your car in the same sense that racing, in general, is “bad” for a car, because it puts a huge strain on the mechanical components, but when used appropriately, no damage will be permanent or irreparable.
How Do You Brake Boost an Automatic?
Brake boosting in an automatic is a simpler proposition because you don’t have to worry about wear on your manual clutch. First, you build up a steady speed of about 20mph, and then gently start to apply the brake. When the brake is in place, then you push the gas pedal all the way down. A speed of 20mph sounds slow for something like this, a racing manoeuvre, but it suits the purposes of the technique very well.
As the gas pedal is down, you have to wait until you hear the spooling of the car’s turbocharger. Once you hear that spooling up, then you can release the brake and experience the rush of power and the boost effect. You’ll hear a lot of engine noise, but the speed boost is palpable and immediate.
Can You Brake Boost a Manual Car?
You can brake boost in a manual car, but some warn that the strain on the clutch and drivetrain components can be too great, not to mention the brakes. The process of achieving the brake boost is much the same as that described further above, but the main thing to remember with manual cars is that you have to do it while in a lower gear to get the proper effect.
Can You Brake Boost a Supercharged Car?
The consensus among racers is that while technically you might be able to perform a brake boost manoeuvre in a supercharged car, but the way that the supercharger works prohibits any real boost from being achieved, especially compared to that of a turbocharger.
A supercharger builds up boost by rpm, but when you boost with a turbocharger you are spooling up the turbo to beat the lag and get that boost when you release the brake. The same effect won’t typically be achieved with a supercharger without some other additional components being used to help like a torque converter. A converter would allow you to launch from a higher RPM, but whether that would give you any significant boost in speed is another question.
Conclusion: Brake Boosting -Good or Bad?
It’s clearly a good racing technique that provides you with a significant advantage while roll racing. When all other things are about equal, that boost of power is just what you need to overcome an opponent and pass them at the crucial moment in the race. Drivers need to be mindful, however, about what brake boosting can do to your car’s brakes and drivetrain components. Don’t hold the effect for too long, nor use it overly often.
Go Home
