$350,000 may buy the first 2010 Camaro, but a few dollars more will buy the first of an ultra-rare Mustang. The track-only 2008 Ford Mustang FR500CJ prototype crossed the auction block last weekend at the Barrett-Jackson Scottsdale auction for $375,000.

Although the Mustang FR500CJ retailed for $70,000 (all 50 units were spoken for in 10 days), this one gets to demand a premium. Unlike the rest of the FR500CJs out there, this car has already been broken in. It was one of two prototypes built to test low-volume car. Drag racers who had wheel time with this vehicle include John and Ashley Force (both of whom signed its hood), Robert Hight, Mike Neff, and Bob Tasca III.

The Mustang FR500CJ is inspired by the 1968 Cobra Jet Mustang. While the original Cobra Jet’s race-inspired engine only made 390 horsepower, the Mustang FR500CJ’s 5.4L V8 from the GT500 makes 428 hp. The car is not road legal, but it is NHRA-legal right out of the box.

.