can my motor and cam be causing no vacuum for brakes or something else?
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long story short, just a 408 in the car with a decent size cam. also deleted abs and put a proportioning valve in it (sjm). now i have bled the lines 4 times and STILL when i press the brake in the pedal goes all the way to floor, then when i let off and press it again the car stops. things i am considering could be wrong.......
check valve gone bad?
master cylinder?
booster?
not enough vacuum?
does a proportioning valve have to be bled?
could use some help guys im stuck on this one and dont want to just go out and buy masters and boosters and waste a bunch of cash
check valve gone bad?
master cylinder?
booster?
not enough vacuum?
does a proportioning valve have to be bled?
could use some help guys im stuck on this one and dont want to just go out and buy masters and boosters and waste a bunch of cash
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Low vacuum should make pedal effort higher, not lower.
Or for same effort, less effect.
Seems more to me like you've got something kicking the
caliper pistons way out from the rotor (needing much more
fluid volume than one stroke can deliver, to engage again)
or maybe some issue like water in the calipers / local fluid
that pushes fluid out when it gets heated. But if this problem
exists when the brakes are dead cold, that wouldn't be it.
If you high-idle it when the brakes are cold, do you have
the problem? Low idle, cold? High idle, hot? Cut away the
stuff that isn't a problem and maybe it'll come clearer.
Or for same effort, less effect.
Seems more to me like you've got something kicking the
caliper pistons way out from the rotor (needing much more
fluid volume than one stroke can deliver, to engage again)
or maybe some issue like water in the calipers / local fluid
that pushes fluid out when it gets heated. But if this problem
exists when the brakes are dead cold, that wouldn't be it.
If you high-idle it when the brakes are cold, do you have
the problem? Low idle, cold? High idle, hot? Cut away the
stuff that isn't a problem and maybe it'll come clearer.
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The car did sit for 3 years while I had the new motor and everything else built. I did the car for a cold and hot drive and it seems like the same thing. I also got the car up to scout 3500 rpms and when to hit the brakes and same thing.