Brake upgrade (running skinnies)

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
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Dallas, GA
I have stock brakes on this car, running 3.5" skinnies and even the stock 88 brakes are more than enough, but it's the back. The other day I was driving and some idiot pulled in front of me, I hit the brakes and all that happened is the front locked up and it was hardly stopping. Now I have flat spotted front tires. :( Anyways, isn't there a brake upgrade for the rear I can do. Possibly a simple disc conversion, proportioning valve, something? Even a more stout rear drum assembly? I'd like disc and if I have to go 5 lug that is fine because I'll just get 5 lug welds or something.
 
I have stock brakes on this car, running 3.5" skinnies and even the stock 88 brakes are more than enough, but it's the back. The other day I was driving and some idiot pulled in front of me, I hit the brakes and all that happened is the front locked up and it was hardly stopping. Now I have flat spotted front tires. :( Anyways, isn't there a brake upgrade for the rear I can do. Possibly a simple disc conversion, proportioning valve, something? Even a more stout rear drum assembly? I'd like disc and if I have to go 5 lug that is fine because I'll just get 5 lug welds or something.

5 lug with Gt brakes would be more than sufficient, pick up a 95 gt rear end, some 95 front spindles, blah blah you know the drill, its almost a required upgrade for the foxes
 
Upgrading the back is not gonna make a huge difference. It does maybe 10-15% of the stopping.

Prob is the skinnies. You could have 13" 4-piston brembos up front, but with a skinny tires, you won't have the traction to make use of it at all. Locking the wheel is a poor way of determining braking power...it just means your tires are crap in terms of grip.

It's one of the reasons a lot of people don't consider driving on the street with big and littles to be safe.
 
Im using SVO rotors and calipers up front(which i think is the same as mark VIII stuff), a MM proportioning valve, and in the rear im using modified stock 94-95 GT brackets, R1 concepts rotors, and stock 94-95 calipers.

Im running skinnies and the car stops just fine for me, panic stops suck with the car, but with the proportioning valve properly adjusted the rears will lock up before the fronts and you will at least have a fighting chance.

FWIW, check out R1concepts for rotors when your ready to buy, i bought them for my lightning, and the rear rotors on my car came from them, i think they were like 90 bucks, for the pair, drilled and slotted plus they are zinc coated so they never rust and look awesome all the time
 
Stppping power is only a function of the grip between the tires and the road.

Those skinny tires have tiny contact patches and low rolling resistance compounds. Perfect for acceleration but horrible for braking.

Your cheapest most hassle-free bet is a set of street wheels and tires for the front.

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Braking power really is a factor of rubber and friction. That's why i always say locking up the wheels is a poor way to determine how powerful your brakes are...it just means you have poor traction.

The front wheels do the vast majority of the braking, and with little rubber on the road, it's very easy to exceed their static friction limit. A lot of these tires uses on skinnies aren't designed with typical street use in mind...they are meant for the track really. As you've come to discover, they have their drawbacks as well
 
Yes but because the front locked up, I just wanted to see if I could upgrade the rear so if it does lock up, it will lock up all 4. The fronts are apperantly more than enough... can't say that about Fox brakes every day.
 
If anything you don't want to lock all 4 up. If you lock the rears, you've lost control and the rear will start to come around on you. It's why a lot of older pickup trucks came with rear-wheel ABS...to prevent the rear from locking.

Put some good wide sticky 245's on the front and try a few panic stops from 80MPH...you'll change your mind quickly about how great stock fox brakes are. Locking up the tires just means your tires blow.
 
Ditch the skinnies for street use. Put some decent street tires at least as big as originally came on the front end of the car: 85% of the stopping power is generated by the front tires.

Lock up the back tires and you find out how fast you can drive backwards when the rear end swings around...:eek: