i have an 87 gta with disc brakes all away around all of the calipers have been changed as well as the pads, the problem is that i almost have to stand up on the brakes to get the car to stop, when you push it you fell the brakes ingage then its like the pedel gives a little when your stopped the pedel holds pressure fine and doesn't go to the floor, also i have tried to slam on the brakes and the car just slowly comes to a stop it really doesn't cause any problem in normal driving but if some dummy pulls out in front of me its all over any help would be great thanks

 

It sounds like you don't have enought friction going on.

Pull the wheels and take some sand paper to the rotors both sides and pull the pads and do the same to them. You can rub the pads on smooth concrete vs sandpaper.

It sounds like the pads and rotors have glazed.

Put it back together and go for a drive in a safe place. You will not have any breaks after doing what I described until you transfer some pad material to the rotor.

Try to do a few (6 to 8) 80% effort stops from about 30 to zero / 40 to zero / 40 to zero / 50 / 60 60. Do these as quick as possible you want to build in some heat. Then drive the car for a few minutes without touching the brakes in order for the rotors to cool off.

If you don't have brakes repeat. Your brakes should get better with each stop as you transfer pad material to the rotor.

 

i have the same problem. the calipers are new so is the master cylinder, and ss brake lines, and when you mash the pedal it goes in 1/2 an inch and the pedal gets supper hard and the car slowly rolls to a stop.

i was bleeding them today and my buddy was pumpin the pedal and i see the calipers flexing underload, plenty of pressure!


the problem happened right after i bought the car the original owner said it needed new pads when he sold it to me. so that week i replace them with autozone pads and the cars never been the same, even the ceramic pads from auto zone suk, im pretty sure it the pads, im finally going to go out on a limb and buy some high perf. pads alll the way around hopefully itll do the trick

 

let me know if it works i was going to try the reply form sdif above and if that doesnt work i was going to replace the master cylinder

 

ohhhhhhhhhhhhhhhhhhhhh my god..............
so i installed my hawk hps pads about 1 hour ago, the instructions state : resurface rotors if needed, mine are almost new... so skip that step

take some 130 grit sandpaper and sand untill the surface looks clean, then clean off with soap and water

install and make 6-10 stops at 30-35 mph using moderate braking pressure
then make 2-3 panic stops from 45 mph, let the car sit and the brakes cool for atleast 15 minutes and ur brakes r good

so i sanded the rotors with 180 grit " all i had" cleaned with brake cleaner and wipped it off with a wet paper towel installed the pads and did the 6-10 stops, prob. 10 and 3 panic stops from 45. i did this all at 11:30 p.m. on an open road, let the car sit for 25 minutes and bam.


on my third stop from 35 mph the front tires locked up....this has never happened before, and the car stopped on a dime


theese were the only pads that i have used that tell u to sand the rotors clean them and properly ware them in, much like SDIF said.

i noticed a major difference on my first stop backing out of the driveway, theese are great pads, and im sure sanding the rotors down helped too


i'm so happy, my car has alays been scarry when it came to panic stops.... will i stop in time or do i see higher insurance rates in my future


i would say that the hawk hps pads are about 2-3 times stickier than the duralast crap i got from autozone and about 2X as sticky as the perf. ceramic pads i took off last time


bye the way the pad were 39.99 at pepboys

i'm pretty sure your car is just like mine evrthing in the braking system works except the friction on the pads/rotors, replace them with some hawk hps and clean the rotors up and you'll be giggling after your third stop


for years i though some how it was a bad or blocked prop valve because i tried 3-4 different pads and a new set of rotors and still crappy brakes
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hold off on replacing the master cylinder, i did mine 2 years ago with new rotors/calipers/ss brake lines and good brake fluid, nothing really changed till now

 

Check the rubber hoses in front. I changed everything else cause I didn't think it was the lines. Finally I replaced them. Funny you could bleed the brakes but when I got the lines off I could not even blow through them. Now it feels like I have all the brakes I need. Stops even and quick. Lets off as soon as I release the pedal. I couldn't believe how much differance the lines made.

 

This sounds like my problem!! I have done all calipers, stainless braided lines, vacuum canister, electric vacuum pump, new master, have a new uninstalled prop valve. Gonna grab some of those pads and a pair of new rotors and have at it!!!