Whoa, Nelly! Your author holds...
Whoa, Nelly! Your author holds on tight as he buries the brake pedal and lets the ABS do all the work.
Last year, I picked up an '07 Mustang GT to serve as a daily driver and a weekend warrior. Immediately, the performance and comfort of the new Stang was quite noticeable over previous generations. Ford did its homework, as virtually every aspect of the car is just right for a reasonably priced modern musclecar. From the 300hp engine to the suspension and interior, the engineers and designers did a great job. But with the good also comes the bad.
As impressed and satisfied as I was with my new Stang, I couldn't help but notice that it suffered from the same problem as every other factory stock Stang-poor braking. While much improved over prior Stangs, the stopping power was inadequate under serious driving conditions. I don't demand a lot from my brakes, since I leave auto-crossing and road racing to other enthusiasts, but with such awesome stopping power available from the aftermarket, I figured there was room for improvement. I expected a bit more bite to help bring this 3,700-pound street missile to a stop in a hurry.
 This was the scene in the...  This was the scene in the staging lanes at Raceway Park-we performed a trackside brake swap in order to produce same-day results. |  The larger rotor on the left...  The larger rotor on the left is standard on Shelby GT500s, while the rotor on the right is a stock Mustang GT component. In less than an hour, we greatly enhanced the stopping power of our test vehicle, an '07 Mustang GT. |  The first order of business...  The first order of business was removing the front wheels. The lugs were loosened with the car on the ground. It was then hoisted in the air with a jack and placed on jackstands. Justin Burcham of JPC racing grabbed the impact gun, zipped off the lugs, and removed the wheels. |
Thankfully, the aftermarket has addressed the situation, and I turned to Ford Racing Performance Parts (FRPP) for an upgrade. Jesse Kershaw of FRPP recommended the company's GT500 brake-upgrade kit (M-2300-S) to help stop the car quicker and add a unique look to it. It's an all-inclusive part number, which means you get Brembo four-piston front calipers, pads, 14-inch rotors, a Goodridge four-piece hose kit, and Shelby pads for the rear brakes. The GT500 brake upgrade fits all '05-present Mustangs, and can be installed in your driveway with common tools.
We must warn you, though, that switching to this brake combination requires a minimum of 18-inch rolling stock. Our test subject had the standard 17-inch Bullitt wheels. On the advice of Justin Burcham of JPC Racing, we selected a set of FRPP Shelby wheels (with black accents). He had cautioned us to be careful when shopping for 18-inch wheels. Apparently, not all wheels fit properly over the massive Brembo setup. The four-piston calipers sit out further than other brake kits, so Shelby-specific wheels should be ordered. FRPP offers three versions of the Shelby wheels: standard finish, standard finish with black accents, and black.
 Here's a comparison of the...  Here's a comparison of the Brembo caliper versus the stock one. The Brembo unit is a four-piston piece that offers much greater clamping force compared to the stock one. |  The stock brakes didn't serve...  The stock brakes didn't serve us well during their 9,000-or-so-mile tenure. |  JPC racing's Danny Kester...  JPC racing's Danny Kester removed the caliper and disconnected the brake line. |
As for tire selection, browsing through our storage room netted us a set of Goodyear F1 GS-D3 tires. Up front, the tires checked in at 265/40-18, while the back was sized at 275/40-18. The wide Goodyear rubber was a vast improvement over the narrow OEM stuff-Pirelli P-Zero Nero 235/55-17 all around. Overall height changed only 0.40 inch when going from the Pirelli tires to the Goodyear F1 GS-D3s. We're not sure if it affected the speedometer; it appears to be reading properly, and we haven't touched the tune. This is important: Since the speedometer is a computer reading, you must update the tune with a drastic tire change.
The F1 GS-D3 tires came out last year and were designed for both wet and dry performance, and to also offer the highest government wet-traction rating with competitive treadwear. One noticeable difference is that the wider tire made the stance narrower on the roadway, and the driver will feel the heavy truck-made grooves a lot more in the steering when on interstate highways. I had a similar experience in the Roush 427R late last year when the MM&FF staff drove that hot rod for a few months.
 The rotor was held in place...  The rotor was held in place by a clip, which was snapped and pulled off. |  Removing the rotors was easy...  Removing the rotors was easy once the clip was out. |  The stock dust shield was...  The stock dust shield was removed and the GT500-specific one installed. |