Cass, AKA Dr Diff, is a great man to do learn from and do business with. He is VERY knowledgeable and helpful.
I installed Firm Feel's front brake pads in the big single piston calipers, and used the Mopar 11 3/4" Police/Taxi front rotors with Cass's rear Econo Kit. That rear kit uses 2005 Mustang Cobra R rear disc's and calipers with a steel mounting bracket. I also run them with the manual < 1" Master Cylinder. I forget the exact bore size, but it is perfect for the combo. I also had Cass order me a complete set of the braided steel DOT brakelines for the system. It makes a huge difference in pedal feel and feedback.
The front and rear discs are perfectly sized and very well-matched to the point that I don't need any additional proportioning control. This brake combo's feedback, balance and feel has been nothing short of amazing over the years.
I also installed one additional item in my brake system that gets little attention on the forums, but is a significant upgrade for braking safety. This < $100 device installs on the rear brake line just before the line split/hose to the rear axle. It is essentially a shock absorber for the pressure spike that occurs when you suddenly hit the brakes. It provides a split second reduction of the initial shock wave in the brake fluid as it travels to the rear discs/drums. It does not reduce the line pressure at all. It simply cushions the initial shock wave, so that the rear brakes don't lock up as a result of the instant increase in brake pressure during panic stop like applications. Otherwise, you would never know it's there.
It works extremely well, is relatively inexpensive and is easy to install. I use it on both my Mopars, which have always had a tendency to lock up the rear brakes during a sudden hard stop, especially when it had drum brakes and stock proportioning.
The device is used by a lot of dirt and asphalt racers for that very purpose. To dramatically reduce initial rear brake lock up during sudden hard braking applications. I'll dig around for the name of the product and post a picture here in a bit.
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