Ford Mustang Cobra Automatic Transmission Swap - When Automatics Attack - Tech

At the track, this '04 Cobra had run a best elapsed time of 10.74 at 131 mph. Smith, who for more than a year hadn't made any passes in the car, jumped in and ran 11.08, riding the brake pedal. "I accidentally left my foot on the brake pedal because I was getting ready to shift the next gear," he says.

We met up with Smith the following week at the first Mustang vs. GTO Shootout in Gainesville, Florida, and our boy made an easy pass in 10.85 seconds at 128 mph. Traction is now an issue as the automatic has transformed the nitrous-oxide's effect on the torque curve. With HP's Tony Gonyon at the wheel, the snake charged to another traction-limited, but better, 10.30 at 130 mph.

Sure, there's plenty left in the Cobra, and Smith managed to take down the top GTO that day at Gainesville Raceway. What's even better is how much more he enjoys the car now.

"I've driven it around for about a week, and it's pretty neat," he says. "It sounds completely different, and I have lots of problems with the street tires now that the torque down low has increased so much."