13" Modern Mustang or Wilwood brakes?

I didn’t know if anyone had played with the 6 piston Wilwood brakes and the late Mustang 13" Cobra brake conversion for the '67 cars with KH four pistons disc. I don’t think the factory power disc cut it for stopping so I was looking at two options. Mustang Steve offers a 13" conversion based on the late Mustang GT 13" rotors. That is a reasonable option at about 500.00 for powder coated calipers and drilled and slotted rotors.
The other option I was looking at was the Wilwood 6 piston caliper set up. I believe it is also 13" rotors.
I have factory power brakes with the Midland booster and factory master. I do NOT want to change the booster or master.
Do the Wilwood brakes work well with factory power?
I was just curious if anyone had any experience with either of these set-ups.


I can’t speak to the conversion kits you are considering but I will advise to stay away from drilled rotors to avoid cracking. Slotted are fine just not drilled.

I to have been looking into brake upgrades as well. Previous owner swapped the ol Granada swap and while they do work I want something better but need to find something that works on those spindles as I do not have the originals. That’s another topic however.

While not having direct experience with these swaps yet I do have some thoughts about them. Unless you drive your car hard enough I think the 13” rotors and 6 piston combo is going to be overkill to the point it may affect braking in a negative way. The pad material tends to need to be hot before you get maximum stopping power. Great for the track but bad for normal driving. The nice thing about Wilwood is they have about every combo under the sun too so they may have something that can tailor to your use.

The other thing to keep in mind would be that you can not resurface a drilled and slotted rotor on a conventional brake lathe. You may not put on enough miles to worry miles to worry about it tho.

I like the idea of mustangs Steve’s use of factory parts to update since you parts availability is going to be easier and more plentiful. You could even afford to buy a spare set of calipers, rotors, pads etc for the shelf.

I have been looking for the mounting bracket to use the T-bird/Galaxie 13" rotors like they did on the TA cars. However, in all honesty it makes no sense to spend 2100.00 for OE parts when the Wilwood will do so much more. I have a 600 hp 427. It needs to stop… Yesterday!
Mustang Steve ( Steve) did my brake pedal support conversion. It’s full roller bearing and it functions so much smoother. Even with the mechanical linkage.
I may call Steve and see if he has a vehicle I can drive that has the conversion to get an idea if the late model mustang 13" brakes are the direction I want to go.


Why don’t you just use the stuff that Cobra Automotive uses on their 600 hp race cars? Plus u can still use 15” wheels if u wanted in the future. If it stops their race cars lap after lap, I’m sure the would be more than enough for the street


Street or Track sells just the Trans-am caliper brackets.
They also offer various kits from 11.25 to 14" with 6 piston calipers.

I can heartily recommend Street or Track here. I bought all my suspension and brakes from Shaun. Great guy, true vintage Mustang racing focus and great support.

Both manufacturers above offer the TA ford set up. It’s 2,000.00. That’s my issue. Crazy money for OE parts with the exception of the bracket.
They have all the part numbers in the Boss 302 chassis modification. It’s just the caliper to spindle bracket that is the variance.


I have the Wilwood 6 piston on the road race Cougar. Works great on the track and I haven’t had them fad yet. They would be overkill for a street driven car, but would add that race car look if that’s what you’re going for. You’ll be limited to 17" or above on wheel size. The amount of pressure being applied to the calipers is also a factor. You’ll want to consider a master cyl with a 1.00" bore or larger and add braided brake lines. The whole system has to match and work together. Can’t leave one piece of the puzzle out of the equation. As stated above don’t use drilled rotors. Slots or no slots are the way to go.

Do the overall piston area math with whatever setup you think about going with. I wasn’t happy with the stock booster and 6 piston wilwoods until I went with a hydro boost. Turns out they have a much smaller area than the stock 1969’s (huge) single piston.

The OE for 65-67 cars is the four-piston K/H caliper. 68-70 use a single-piston caliper. The braking isn’t as good as the previous year four-piston. The pricing from the other suppliers more than I care to spend for factory parts. They are ideal as far as application. They’ll look stock.