Brakes are really important. They could mean the difference between being in an accident, or avoiding an accident. I've always been a big fan of stopping power. There came a time where I needed to change my brakes in the 94 GT Convertible. I had just recently bought the car, so my great idea was to go budget. The brakes are already 'good'. I'll just get the rotors cut and put some cheap pads on there. That's exactly what I did, and I did it for less than 100$ for all four corners. I took the car out, bedded the brakes and began using them. Everything seemed fine to me. Some time during my lovely 74 mile commute to work, I needed to execute a panic stop. I came around a blind corner going 70MPH and traffic was absolutely stopped. I jammed on the brakes and after about 3 seconds, fade crept in. For those that don't know, fade feels exactly what it sounds like - the brakes almost feel like they get wet and slippery. This is due to a build up of gasses between the pad and rotor. Another root cause is the pad material. I needed to do some pumping of the brakes and some serious downshifting in order to stop in time. After that, I didn't really trust the brakes anymore. Time for an upgrade.
One of the common bolt-on upgrades for the 94 mustang GT is 1999 to 2004 front calipers. They are called PBR calipers, and they are dual piston. the two pistons add up to more stopping power than the single large piston caliper that came stock on the 94. I found a set of good working used PBR calipers and had them shipped to my house. I also had a set of stock rear calipers on the shelf - they were for another project that never came to light. I did some research on brake pads and everything was pointing to the hawk HPS pads. I also wanted to do some cross drilled and slotted rotors on the car. I found a company that gave me a great deal on the four rotors and pads for my car so I ordered them. I also needed to get new front brake lines, so I decided to upgrade the rubber lines to braided stainless steel. I ordered the stainless steel braided brake line kit from summit. I dont remember what the part number or manufacturer was. Probably Earls Performance.
At this point I had front and rear calipers, front and rear hawk HPS pads, Front and rear cross drilled and slotted rotors and the stainless steel braided brake lines. I decided to get a fresh coat of paint on the calipers. I took the calipers over to my friend's house who has a sand blasting cabinet. We spent some time chasing the threads in the brackets and on the bolts. We also taped off the important areas and into the cabinet they went. When they came out, they looked fantastic! I'll note here that we really don't use sand, its shards of glass. I picked up a bucket from McMaster Carr for my buddy since he helped me out. I took the calipers home, and gave them a few coats of Dupont black engine enamel. I gave it some time in between coats, and hung them in the garage to dry.
Finally it was time to do the install. Everything went very smoothly. The calipers were remove and replace, the rotors were new, there were no surprises. The step was bleeding the brakes. After that was done, I installed the wheels and tires, torqued the lugs and it was off to bed the brakes. The idea is to go from 50 to 10mph without coming to a full stop. This was repeated 5 to 8 times. Then, I need to drive around - not using the brakes is preferred - to let them cool for about 5-10 minutes. The brakes should have a 'bite' to them after the third full stop. This was not the case for me. After the fourth stop, I realized that something wasn't right. The brakes felt better, but it just didn't throw me out of my seat like I expected.
I opened up a discussion thread on the Corral.net to hopefully get to the bottom of it. About a day into the discussion, we found the problem. The master cylinder in the 94 GT is TOO BIG for the 1999 GT calipers. The 1999 mustang used a smaller master cylinder so the root cause was a mis-match between the calipers and master cylinder. I could either put the stock calipers back on (which means I also needed different brake pads) or I could change my master cylinder. I chose to change the master cylinder. It turns out that the 1993 mustang cobra master cylinder was the perfect match. I bought one from RockAuto.com and installed it. Of course it was nice to bleed the brakes yet again. The difference was night and day. The stopping power I had now was way better than it had ever been. Brake upgrade - Complete.
One more thing to note. The hawk HPS pads create a lot of brake dust. I have 42k miles on this set up and its getting close to me needing to replace the front pads again. I went through the same company and installed the cross drilled and slotted rotors with centric posi-quiet pads on my 04 Expedition when that needed the brakes done. There's really no brake dust problem there. In hind site, I should have went with the posi-quiet pads instead of the hawk. The hawk would have been a great upgrade if I was not going with the cross drilled and slotted rotors. I'm still up in the air about replacing the front AND back pads in the mustang with the posi-quiet pads for 70$ shipped OR just replacing the fronts with the hawk pads for 80$ shipped.
Stay Tuned!
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