i recently did a disc conversion and my brake pedal moves on its own when i rev up the engine...has anyone ever seen anything like this ...i bought a new booster and master for the system thinking it was a bad booster but no different and have a cam that doesnt need a stall converter but isnt no slacker and running a tuned port for induction and have good brakes but the brake pedal moves on its own up to a couple of inches it seems and it has the spring on it...any ideas ?? this is driving me nuts!!!!

maybe too much leverage/not enough angle on the pushrod? this would make the pedal seem 'heavy' to the booster/master and make the pedal go down on its own.
though there should be a check valve for the booster to hold a somewhat constant vacuum inside it, in which case it would go down like that as soon as you apply vacuum to it, is your booster hooked below the throttle plate like it's s'posed to?
err. dunno

Make sure you have a little free play in the booster pushrod, or the brakes will be a little bit "on" all the time and will be affected by the amount of vaccum.
David

hmmmm-- yep that sounds right...ill give it a wirl and see what what happens...i should be able to feel the play in the rod atached to the pedal anyway.. graemlins/clonk.gif graemlins/thumbsup.gif