I noticed when I had my car in the air and was going through all the gears after my shift kit install....that I had no back brakes....I stood on the floor and nothing.......I pulled the ebrake handle......nothing.......I did bolth at the same time........nothing..........the wheels slow down but I cant stop them

These are ordinary Disk Brakes not drums...

I machined the badly grooved rotors and put on new pads and bled the back brakes........nothing

Why wont my back brakes work!?
Im loosing some Free ET....I been 13.03 but I can only torque the car up to 1000 RPMS on the line because only the front brakes are holding her back.....I could launch way harder if my back brakes worked right......

Does anybody have a clue why they wont work?

The pedal is hard as a rock and doesnt sink.......

Im stumped please help me!

 

Your back brakes are only doing 20% of the work, therefore you probably will not notice them doing much at all.

This is normal sorry to say.

 

your sure they weren't disabled b/c of line lock or something?

 

No I bought the car used and very abuse and running 15s......not owned by a performance enthusiast....There is no line loc .....and I had my car on jackstands and put the car in drive.......I could not hold the back wheels from turning.....I'm sorry thats not right...
Oh yeah and also u should be able to lock up or chirp the tires when u firmly hit the brakes at 10mph......I can lay into the pedal as hard as I can and the car glides to a stop.

 

That would have been good to know earlier. Does the pedal feel spongy at all??? Is it hard to press in??? If you SLOWLY depress the brake pedal, will the pedal move to the floor with the car in Park???

 

No, The Pedal is firm as a rock and doesn't sink

 

uhh, till you get this whole thing sorted out... if you see me on the road... try to keep your distance... pwease?

 

lol yeah I would like to trust me....I could be launching at 1800 RPMS instead im launching at 1000 cause i have no back brakes......thats probably cutting a tenth off.....I coulda had 12s damnit!

 

mmmmm maybe... our back brakes are only 20 percent

 

I disagree I went to a trade school for 3 years and was told back brakes are about 40% of your braking ability.

Either way they should at least hold the back wheels from spinning at idle!!!

 

Actually it changes from vehicle to vehicle. You can't just say ALL CARS use 40% back brakes. On our cars, they use 20% rear brakes and 80% front brakes.

 

You said that you had the BADLY grooved rotors turned.....were they tapered? Are you sure they didnt get machined too thin?

 

I assume none of the calipers are stuck.

 

If the car was abused, the calipers may have gotten hot and stuck. Especially since you say you had to have them heavily turned.

-shannon

 

ya, I have the exact same thing going on with my 1993 Z. I replaced rotors, pads, bleed brakes twice, adjusted them and still the car is doing exactly as you describe My emergency brake won't even hold the car at idle. If I'm up on car ramps and try to back off, and lightly apply the brakes, the front tires grab the ramps and drags them back with the car.
I have just come to the conclusion that this must be how they work If you figure it out please e-mail me and I will do the same.