Trail-braking: the act of carrying brake application through corner turn-in. It can be long or brief, depending on the corner and the car’s setup. Trail-braking allows a driver to brake later by extending the braking zone into the corner. It also improves the car’s turn-in response by increasing load on the front tires to maximize grip. Together, these result in higher corner entry speed and reduced time through the corner.
Without trail-braking, a driver brakes before the corner, releases the brake and turns-in with maintenance throttle for steady-state cornering. In this scenario, the demand on the tire spikes during braking and trails off before increasing again for turning. With trail-braking, the majority of braking occurs in a straight line with brake release initiated at turn-in, continuing through the initial phase of the corner. As such, the tire is used to its full capacity through the entire braking, turn-in and cornering phases. An added benefit of improved turn-in response is the potential to turn later, rotate and then straighten the car to apply throttle sooner.
The most important part of any braking is to slow the car to the ideal cornering speed. Trail-braking complicates this by blending the braking and turning. Too much or too little trail-braking can cause a car to understeer. First master the brake release: easing off the brake before turn-in to avoid losing front load and grip when needed most.
Start with a consistent brake reference and brake pressure. Build confidence by easing off the brake sooner and carrying more speed into the corner. Practice progressive steering input: steering more as the car slows to use all available grip. As you get comfortable carrying speed in, begin moving your brake application and initial release closer to the corner. The ideal trail braking occurs when initial brake release occurs at the initiation of turn-in. Continue to release the brake and increase steering down to the apex. Release the brake completely and unwind the wheel to roll on the throttle at exit.
The extent of optimal trail-braking depends on a vehicle’s setup. Trail-braking can help the car rotate and cure any tendency to understeer at turn-in. A car that tends to oversteer at turn-in will require more stability and less trail-braking. Additionally, some corners require more trail braking, and others less. As with all techniques, trail-braking is a tool to achieve a desired result. It allows a driver to carry more speed into a corner and still hit the apex for early throttle application. The drivers’ ability to trail-brake often makes the difference where they stand on the podium.
A mechanical engineer and driving coach, Joshua Allan has worked in the design offices of Ferrari’s Formula 1 team and has been a vehicle development driver for Maserati in Italy. He is a five-time Performance Touring National Champion in a Mazda MX-5 with Robert Davis Racing. Send questions for future articles to [email protected].