The proliferation of Pro Touring cars, G-machines, or whatever you want to call cars built to do everythcing well has been made possible in large part by the development of bolt-on aftermarket brake kits. Baer, Brembo, Stainless Steel Brakes, and Wilwood are the big players, but credit Baer with really ramrodding the aftermarket scene with affordable big-brake kits a decade ago.
Before the days of aftermarket options, if you wanted good binders on your drum brake-equipped musclecar, you had to either scrounge for junkyard parts or spend big money on full-race brakes. The factory-swap parts were the cheapest, but the braking results weren't all that incredible-they were as good as '60s and '70s factory disc brakes. If you were one of those people on the cusp of the Pro Touring trend and actually wanted to punish your brakes on a road course, the factory stuff just didn't work that well. You had to go with a racing-type brake, which often didn't have the seals and all-weather durability necessary to live on the street.
We have it easy today, thanks to the companies mentioned earlier. But how good? Hot rodders have been conditioned to believe they need big aftermarket brakes to retain respectability, but are they really that much better than factory discs? Are they worth the money? We put Baer's most real-world brake kits to the test to find out.
Our test subject is a nice but relatively stock '65 Mustang coupe. Originally equipped with four-wheel drums, the car had an upgrade years ago to a factory-style front-disc setup. This used the same 10-inch rotors and four-piston Kelsey-Hayes calipers that you could get as an option on early Mustangs, along with a single-reservoir master cylinder with a power booster. The rear drums were left stock. Though the brakes worked, they were a long way from inspiring confidence, with a spongy pedal that required serious effort to stop the car in a panic situation. The brakes were worse the harder you stepped on the pedal, and you couldn't get them to lock the wheels no matter how hard you stood on it. There was not a single air bubble in the system, and the cam in the 283 is excessively mild, but we never could get a firm pedal and hard-hitting brakes.
When it comes to brakes, bigger really is better. Bigger rotors give the caliper more leverage and therefore more ultimate stopping power, but obviously you have to work within the space limitations of the wheels. Fourteen-inch rotors need 18-inch wheels, and 13-inch rotors usually mandate at least 17-inch rims. In addition to increased leverage, big brakes are far better at resistance to fade since they represent a bigger heat sink. Unless you plan on really abusing the car on a road course, fade won't be that much of a concern on a street car. For those with 16-inch wheels, a better choice is a 12-inch rotor. If you're stuck on factory 15s, consider Baer's Serious Street kit with 11-inch rotors that clear most factory wheels. Our Mustang had 16x8 Edelbrock five-spoke wheels (made by Ultra but now out of production) that we like, so we went with Baer's Sport kits with 12-inch rotors and two-piston PBR calipers. In a street situation, you'd be hard-pressed to get these brakes to fade. This is the same kit required for the SCCA's tough A/Sedan class, so you know it's robust.
Installation was handled by Marlo's Frame & Alignment in Chatsworth, California, and was pretty much a no-brainer because Baer included almost everything necessary-although we did get an adjustable-pedal pushrod from Scott Drake Reproductions that allowed adjustment of the pedal height. It all went on in a day, including bleeding the system and bedding the pads.
Before we installed the Baers, we beat on the little Mustang's stock-type brakes repeatedly at Buttonwillow Raceway, making about 15 stops from 60 mph. The longest distance recorded was 195 feet, and the shortest was 155 feet. Though we expected the stock brakes to fade horribly with the heat of repeated use, shockingly the last four stops were within 10 feet of each other. Averaging the last three stops resulted in 159 feet as our baseline.
After we installed the complete Sport front and rear kits, and with the rotors seasoned and the pads bedded (two vital aspects of the installation of any rotor and pad kit), we went back to the brake test. The first time we stood on the brakes it became very apparent they were much better at stopping the car. So much better, in fact, that they caused the car to go into a pretty serious wheelhop that made pedal modulation crucial. It took about five stops to get a feel for it, but we still got only two stops completely devoid of hop. Those were in 129 and 133 feet. Throwing out the worst two and averaging three of the best brought us to an average of 137 feet.
At the urging of Marlo's, we installed the kit without a proportioning valve in the rear lines, and that may be part of the wheelhop problem. We're going to install a prop valve and experiment with it, and we think we can knock more feet off the stopping distance by dialing out some aggressiveness in the rear brakes. Baer's Todd Gartshore said that when the system is set up perfectly and you're executing perfect threshold braking, it will typically lock the rear brakes the last 7 or 8 feet of the stop.
Still, 22 feet is more than a car length and could be the difference between a safe stop and plowing into the back of the car in front of you. As for pedal feel, we were a little worried about it since we had to go to a manual setup because the shock tower won't clear a booster and dual-reservoir master cylinder. But the new pedal is far more confidence-inspiring than the mushy old power system. It requires a little more effort initially to get the brakes to grab, but it's much more linear and easier to modulate than the power system.
The cost for the front Sport kit is $1,235 and the rears go for $995, so you're looking at just over two grand. Is it worth it? In our opinion, absolutely yes. Twenty feet might not sound like a huge difference, but it really is, and when you combine it with an easier-to-control pedal and complete resistance to fade, even on this street-only Mustang it's well worth the price. On a car that might see some open track days it would be even better. Do it.
