 The braking system was designed by AP Racing and featured ventilated and cross @-@ drilled discs of 13 in ( 33 cm ) diameter at the front and 11 @.@ 8 in ( 30 cm ) diameter at the rear . The calipers are four pot aluminium units . JaguarSport designed the handbrake , which are separate calipers acting on the rear brake discs . Feedback from enthusiasts and racing drivers resulted in the decision to drop the anti @-@ lock braking system from the production car . The braking system was installed without a servo , but a number of owners found the brakes to be difficult to judge when cold and subsequently requested a servo to be fitted . 
