2003 Ford Mustang Cobra Modifications

With the factory blower and bolt-ons, the Cobra put down 476 hp to the tires. To accurately gauge the gains of the turbo system, HPP also dyno'd the car in naturally aspirated trim, which yielded 305 rwhp. While it's no secret that turbos run more efficiently than blowers, Manny's Cobra resoundingly reinforces that point once again. On 93-octane pump gas, the turbo Cobra laid down 515 hp at 9 psi of boost, 560 hp at 14 psi, and 680 hp at 16 psi. Adding a bottle of Torco fuel accelerator allowed 19 psi, for 820 rompin', stompin' horsepower to be unleashed. "It's hard to believe, but a bottle of Torco for every 5 gallons of gas will raise the octane rating by seven to eight numbers," says Manny. "People are amazed I can make this much power on pump gas. They see me filling up with 93 octane at the gas station and ask,'What are you doing?'"

Despite the stock IRS' propensity to explode, Manny somehow found a way to make it survive. He utilized a pair of Level 5 halfshafts from The Driveshaft Shop, a Billetflow differential brace, and Maximum Motorsports aluminum bushings to keep wheelhop in check. Even the factory Traction-Lok has yet to give up. Further upstream in the driveline is a Ram twin-disc clutch bolted to a Fidanza flywheel. The T56 has been fortified with a heavy-duty 26-spline input shaft out of an Aston Martin but is otherwise stock. Overall, the simplicity and durability of the driveline is arguably even more impressive than the stock long-block.

So what does it run? With the boost cranked up to 19 psi, the Cobra ran a best of 10.10 at 137 mph on a brutally hot and humid Texas summer day. Single-digit e.t.'s are a given in more hospitable air, and mid-nines are entirely feasible with a stalled automatic trans. Track heroics aside, Manny loves driving his car every day-on Mickey Thompson tires-and regularly takes customers out for joyrides. "I burned through a set of ET Streets in less than a week," he says. They've been replaced with 335/35-17 Hoosier drag radials, but the meats still spin prodigiously at 100 mph on the freeway. "I've been beating the snot out of the car for 6,000 miles since the turbo upgrade, and the car loves it. It's begging for more." Whenever the stock engine decides to expire, plans call for a stroker motor and even more boost. Gulp.