14 bolt disk brake question

[k5-newbie]

got my rear disks on and the lines ran, also added a master cylinder from a 79 corvette (stock 4 disk brake mc) now my question is do I need to run a proportioning valve? my brake pedal is really mushy and Im gonna change all the front (D60) pads and calipers this weekend. Any ideas??

Thanks

 

[jekbrown]

you may need to keep bleeding and/or get it power bled at a brake shop if the pedal is feelin' spongy. Not sure on the prop valve... some people need them, others don't.

j

 

[short sub]

weve done alot of trucks with discs all around on a 60/14 combo and none of them needed an aftermarket proportioning valve- it may take some time to bleed them but once bleed properly they have all worked awesome. with a mushy pedal it sounds to me like there is still quite a bit of air in your lines. GOOD LUCK later Ryan

 

[WARP1]

A proportioning valve adjusts the brake bias (amount of braking force applied) between the front and rear brakes. When I swapped out the drum brakes on my car and truck the rear brakes ended up doing most of the braking. The rears would lock up easily under braking. The fronts should do most of the braking since the cars weight transfers to the front wheels under braking. If you just have a mushy pedal that's probably something else. Once it is worked out let us know if the Corvette master cylinder negates the need for a p-valve.

 

[blazinzuk]

Dude just keep on bleeding them, then when you think you are done bleed them again then when you think you are done do it again, repeat this process about a billion times (at least in my case it was) and you will be fine

 

[wraenking]

hmm.. why not spend the 80 bucks and get the p valve? i tried to bleed the hell out of them first and ended up blowing my master cylander.

also, if you are usinf caddy calipers, you have to have the e brake levers adjusted properly or you will always have that soft pedal.

try here for the e brake lever adjustment


http://www.tsmmfg.com/Troubleshooting.htm#2

 

[k5-newbie]

the calipers are not caddy calipers, they are 3/4 ton 4x4 chevy front calipers.