well, actually they use proper design of the braking system. ie discs on both ends of the car.

i believe the usual application of the prop valve is when you have drums on the rear (to save $) and discs on the front.

so the answer nothing is correct in respect to the use of a prop valve.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.