Mustang Forums - View Single Post - Cobra vs. Bullit vs. Stock GT brakes, are they worth it? lets find out.

spike_africa · 05-30-2006, 12:56 PM

OK so the big thing is to upgrade to cobra brakes to get the 13" rotor with dual piston calipers. Now my car is getting to the point where i need to upgrade or freshen up the stock brakes. So i wanted to see how the stockers compair to cobra brakes.

Stock GT brakes on a coupe stop the mustang in 135 feet from 60mph.
Stock 2003-2004 cobra brakes do it in 116 feet from 60mph.

Thats a 19 foot difference, which is just over the length of your car (about 16 feet total for us), but still a large improvement.

Bullit kits are listed as 125 feet from 60mph. Even less of a difference. This is due to the bullit not having the exact same caliper as the 03-04 cobra which is said to have bigger pistons and gives more stopping power.

So considering all of this is it worth it to upgrade for a mear 10-19 feet of stopping power?

I think so, it gives you over an entire nother length of your car plus some with the 03-04 cobra kit. This could be the difference of a truck rear end or stopping and not hitting them.

Now some of the difference comes from the fact that the cobra,bullit,mach1 cars have 13" rotors, which give you more levrage to stop the car. Here are stock Sizes for all cars.

99-04 GT rotors are 10.8" Front and 10.5" rear
03-04 Cobra's are 13" front and 11.65" rear.
Bullit rotors are 13" front Cobra Spec Rear.
Mach 1's are 13" front Cobra Spec Rear.

The cobra's do have larger rear rotor's but the gain in stopping distance is none. The biggest benifit is the vented rotor (unlike all other cars) and the larger rotor cools off faster and make brake fad less.

When upgrading to 13" new front rotors you will need the fallowing:
13" rotors (two)
2 new calipers (this is where cobra,bullit,mach1 comes in)
2 cobra,bullit,mach1 brake lines (Gt will not work)
New Caliper brakets (GT will not work with new calipers)
New Banjo Bolts for calipers.

Of course you can buy these all used also. Most kits are anyhwere from $360-$450 new for front kits.

For the Rear Cobra rotor upgrade all you need is as fallows:
new 11.65" rotor (two of them)
New caliper mounting braket (two again)
thats it.

Any more info anyone has please share. I wanna make this into a starting point for brake upgrades and possibly a sticky.

READ DOWN FOR MORE INFO ON BRAKES

05-30-2006, 12:56 PM	#1 (permalink)
spike_africa Administrator Join Date: Sep 2004 Location: Orlando,Florida Posts: 7,406	Cobra vs. Bullit vs. Stock GT brakes, are they worth it? lets find out. OK so the big thing is to upgrade to cobra brakes to get the 13" rotor with dual piston calipers. Now my car is getting to the point where i need to upgrade or freshen up the stock brakes. So i wanted to see how the stockers compair to cobra brakes. Stock GT brakes on a coupe stop the mustang in 135 feet from 60mph. Stock 2003-2004 cobra brakes do it in 116 feet from 60mph. Thats a 19 foot difference, which is just over the length of your car (about 16 feet total for us), but still a large improvement. Bullit kits are listed as 125 feet from 60mph. Even less of a difference. This is due to the bullit not having the exact same caliper as the 03-04 cobra which is said to have bigger pistons and gives more stopping power. So considering all of this is it worth it to upgrade for a mear 10-19 feet of stopping power? I think so, it gives you over an entire nother length of your car plus some with the 03-04 cobra kit. This could be the difference of a truck rear end or stopping and not hitting them. Now some of the difference comes from the fact that the cobra,bullit,mach1 cars have 13" rotors, which give you more levrage to stop the car. Here are stock Sizes for all cars. 99-04 GT rotors are 10.8" Front and 10.5" rear 03-04 Cobra's are 13" front and 11.65" rear. Bullit rotors are 13" front Cobra Spec Rear. Mach 1's are 13" front Cobra Spec Rear. The cobra's do have larger rear rotor's but the gain in stopping distance is none. The biggest benifit is the vented rotor (unlike all other cars) and the larger rotor cools off faster and make brake fad less. When upgrading to 13" new front rotors you will need the fallowing: 13" rotors (two) 2 new calipers (this is where cobra,bullit,mach1 comes in) 2 cobra,bullit,mach1 brake lines (Gt will not work) New Caliper brakets (GT will not work with new calipers) New Banjo Bolts for calipers. Of course you can buy these all used also. Most kits are anyhwere from $360-$450 new for front kits. For the Rear Cobra rotor upgrade all you need is as fallows: new 11.65" rotor (two of them) New caliper mounting braket (two again) thats it. Any more info anyone has please share. I wanna make this into a starting point for brake upgrades and possibly a sticky. READ DOWN FOR MORE INFO ON BRAKES __________________ Dustin 2002 GT Mustang 5-Speed Drag Radials,Sprayed,Powershifted WOOO HOOOO!