I had a recent conversation with Bill Howell who worked for Vince Piggins' group and was directly involved as the Chevy liason with Trans-Am from 1968-70. Part of our conversation touched on the subject of brakes and here is some of what he said...
"Penske ran 2 cars in the 68 Sebring, both with 2X4's. We won the Trans-am part of [the 1968 Sebring race] after getting tromped by the Fords at the 24 hr of Daytona. We beat them mainly with a brake pad change trick I developed between Daytona and Sebring. It took a year or more for Ford to figure out what it was. It was a simple idea where we applied vacuum to the master cylinder to draw the disc brake pistons back into the calipers, releasing the pressure on the pads. We took the vacuum off the brake booster. We tapped off the brake booster thru a vacuum switch (same as used on the old Corvette headlight doors), controlled by a switch on the dash, then to the cover over the master cylinder. [Coming into the pits] they did need to blip the motor to get vacuum into the booster. Only the Penske cars were equipped this way, as I took the hardware with me when I went to Sebring before the race weekend to keep it secret. The system was mentioned in Van Valkenburg's book. The reason it took Ford so long to figure it out was it was so simple, and most people thought that if you put a vacuum on the brake calipers, it would suck air past the seals and into the fluid."
