In its development of the F1, McLaren Cars worked closely with Brembo of Italy to develop exceptionally high-performance brakes using, for the very first time on a production car, Formula 1-type “monobloc” aluminium four-piston callipers, clasping the latest road-useable ventilated discs. Fully divided front and rear hydraulic circuits are actuated by the Formula 1-style floor-pivoted pedal, while the F1’s lightweight aluminium handbrake calliper has also been specially developed by Brembo.
Slowing such a supercar safely and efficiently from near maximum speeds demands considerable brake cooling. Normally, such a high-speed cooling requirement becomes a problem at low and medium speeds, reducing disc, calliper and pad base temperature excessively between applications. Consequently, the McLaren F1 now introduces “intelligent” brake cooling.
With speed and brake application sensors feeding an electronic control unit, brake-cooling air intake ducts open automatically only when the driver makes a sufficiently demanding application. Since closed brake ducts create no drag, they improve the F1’s aerodynamic efficiency. Furthermore, the system enhances braking “feel” for the driver by sustaining comfortable pad and disc base temperatures during enthusiastic motoring.
In contrast, two conventional areas of modern road car development which actually degrade driver feel and feedback are power brake assistance and anti-lock braking systems (ABS). By developing the F1’s brakes along Formula 1 lines, and particularly by achieving the project’s exceptionally low target weight, power brake assistance is unnecessary.
With the automatic aerodynamic Brake and Balance ‘Foil feature, braking effect and driver feel are improved, since its downforce enhancement then assists the driver under heavy braking by increasing the load on each wheel.
Deploying this BB ‘Foil exposes rear-brake cooling intakes to control the extra heat being generated by the brake application. BB ‘Foil operation is an entirely different principle to anti-lock braking, which maintains tyre adhesion by releasing application on imminent lock. Instead, the McLaren F1’s new system evenly increases tyre load during braking to postpone the onset of wheel locking.