Brakes, alongside tyres, are probably the most important component of any racecar. Even Formula E, which tried to dispense with rear brakes for Gen 3, quickly realised that a mechanical means of retardation is still useful to have.
Since Dunlop first brought its disc brakes to Le Mans with Jaguar in 1953 (though the British company was not the first to see the benefits of caliper brakes), the basic principles of operation have not changed, but the level of optimisation has gone through the roof.
One only has to look at a Le Mans Hypercar, capable of completing a full 24-hour race on the same set of discs and pads, to appreciate just how impressive modern motorsport braking technology is.
Caliper consistency
Imagine a brake caliper as the letter C, with pistons mounted at both ends. When the brakes are engaged, the pistons apply force against the disc, causing the caliper to try to open up. This means that a portion of the force applied by the driver at the pedal is lost due to deflection in the caliper body. This deflection not only diminishes the efficiency of the driver’s brake inputs but also introduces the possibility of a ‘soft’, or inconsistent, pedal sensation.
Furthermore, the caliper can also experience deflection due to the twisting force generated as the friction between the brake pads and disc intensifies. When this occurs, the pistons are pushed back into their bores, displacing the brake fluid. Consequently, the driver must release the pedal pressure to compensate for this, or else the brakes may start to lock up. By maximising the stiffness of the caliper body, the impact of this flex on the braking system’s feel and performance can be minimised. The outcome is a significantly more precise brake feel for the driver.
Building a stiff caliper has to be balanced against a host of competing
