Why the fuck does my car lock the front tires?

[Southern_Pride]

Some dumbass lady bitch pulled out in front of me when I was doing between 50-60 mph. So I panic and hit the brakes. Guess what? They lock up. I have performance tires and the front wheel tires combo is about 70lbs. 26" tall tires. They don't lock up with the claws on, but did with the continentals. My claws weigh about the same. Fuck lowering this thing. Im just gonna go back to big tires when I trash these. I need another 100 horses or so, gears and a posi. And fuck the 5 speed. I'll break it, Ive got a good aod layin around and Ive got better mods to spend money on. Sorry I had to rant.

[mrltd]

the brakes are garbage. Every single car, except for the 87 (and now the wagon) would do that...in fact that's why my 89 is no more. Rear discs would help by taking some of the strain off the fronts. Pads and other things contribute to it also.

[Southern_Pride]

How can they be garbage? I fail to see how a bigger rotor with more leverage will make it harder to lock up the tires. Ive got the best pads they had at autozone and 6 month old rotors.

[Blaze86Vic]

Misconception. They are supposed to do that, it is the design, and is the way it should be. If you locked up the rear wheels then you would lose control.

While braking, a wheel that is locked up is providing less stopping force than a wheel that no locked up.

With the front wheels locked and the rear still slowing, the car will continue in the direction it was going, because the rear is pulling the car to a stop, so it will stay pointed the way it is going.

With the rear wheels locked and the front wheels still slowing, the front it providing more of the stopping force, so the rear will come around and out goes any control you had.

This is something I learned in my race vehicle dynamics class. I too always thought the other way around, but now that I know better I find it somewhat moronic that I ever thought otherwise.

[mrltd]

Stock size brakes are inadequate. Also, alignment and bad suspension parts exaggerate the problem.

As for your racing dynamics, yes. You are correct. Ever look at a 93 mustang cobra? Aware of the differences in the brakes on those? I ran a 93 cobra setup on a 4 cylinder stripped down mustang coupe I could slam the brakes on at any speed in the rain and it wouldn't pull or lockup. Ask eric how his car stopped with the rear disc only upgrade....

Rear disc would help. upgrading to the PI calipers on the fronts would help also. Learning the braking threshold helps even more-but regardless of the possibility of you being able to modulate the brakes and keep them from locking up, the brakes will just fade away...

And locking the front brakes is worthless, less braking force, and loss of steering control, not exactly the way to have a controlled stop.

[Freshmeat]

Continentals suck. I had a set and couldn't get them to stick for the life of me (almost literally a couple of times). I gave them to the Mexicans up the road and bought new tires. This was a few years back.

[gadget73]

The stock 10" drums are also kind of sad. When my car had stock brakes, (remember I have 11" rear drums) the fronts would lock and the back would threshold. Now, the back brakes (still 11" drums" lock right up, and the fronts will not. I can stop a lot quicker but it needs more braking area in the back.

[Blaze86Vic]

I'm not saying locking wheels up is better, but if you are trying to get your rear brakes to lock up first then you are DEAD WRONG! ALL VEHICLES race or otherwise are supposed to lock up front wheels BEFORE the rear.

Obviously the exact balance of front and rear braking force is ideal, but also impossible to have for every situation. So you design the front to be a little stronger for safety.

[gadget73]

I never said I was trying to, it just happens. The brake balance is way off with the stock rear drums and the big front discs. Slam the brakes and the back tires will lock. Its just what it does. Rear disc brakes will fix that.

[Southern_Pride]

My suspension isnt really inadequate. Its police springs in front, wagon rear with pi shocks front and wagon rear. My continentals stayed on for 2 weeks btw. And I dont see the brake size could be to small if I can lock em at 50. I do understand about the braking threshold, but in a panic situation its hard to remember that stuff. And considering I did crash it into a toyota today, I was all the more freaked out. Did no damage to my car, scuffed the dirt off the front bumper. I called the cops but after 20 minutes of waiting for highway patrol he didnt want to wait anymore. So he left and he has none of my info. when these tires are gone Im going to a 275/60-17 in the front, like I have in the rear.

[mrltd]

my 68 F100 would lock the brakes up also, 4 wheel drums. They were not good.

Johnnie, do you think the rear discs are more substantial than the stock 11 fronts? They are not, so there still is more braking being done by the front, but the bias is better than the drums, or at least the discs do not fade as quickly as the drums so you have a more consistant braking. We are argeeing one this, I am just saying that the rear disc upgrade does have benefits-even with stock fronts. (Think 92-97 panthers!!!!!!)


As for the suspension, didn't you say the bushings were shot? Under braking the caster, camber, and toe will all change and reduce grip of the tires.

[Southern_Pride]

Only the passenger side upper ones. It used to throw the camber off but has since fixed it self, like everything else on this damn car. Trust me I know all that changed. I hit em hard enough I bottomed out the front end. There was shiny spots on the frame where there used to be dirt. Maybe the 6 inch drop in height and way fucked up camber is whats doing it. The claws tread flexes and these dont. Even so the claws have tread on the sidewall. Hmmm. Right after I put these brakes on with my firestones I didnt have this problem but I was and inch off the bumpstops. Not much change in geometery. You may be on to something here.

[Blaze86Vic]

I was just clarifying what I said, I believe ya Mike. But just wanted to make sure no one read this and got the wrong message and tried to get their rear brakes to lock up first. Anyone that made their car like that would be putting themselves at serious risk. Which means, GADGET!!! Fix your car!

[boXman]

Scott fixed me up good, my front wheels haven't locked up for a long time...and I have stock shit.

[88grandmarq]

if the stock brakes are working properly, you should NOT lock either front or rear wheels under panic braking.
make sure the rear brakes are adjusted and working properly, also make sure the front calipers are not sticking and the hoses are in good shape.
obviously good tires have a lot to with braking as well.
also a larger tire diameter reduces braking leverage, making them less effective and more inclinded to lock the wheel.

A rear disc conversion does help how the car stops and seems easier to control under harsh braking, more rear valve would probably help

Mike, I dont think comparing brakes on a fox body car is an accurate comparison. Fox body cars have some suspension geometry problems that keep the brakes from working well by any means.