The 2007-2009 Shelby GT500’s are rated at 500-hp at the flywheel, while the GT500KR’s and the 2010’s are rated at 540-hp. New in 2011 is a 550-hp GT500 all-aluminum motor, which is also 102-lb lighter than the outgoing year.

The 500-hp at the crank typically works out to 425-hp at the rear wheels. In comes Paul’s High Performance, who offers the PHP Stage III Performance Package, good for another 120-hp and similar torque gain at the rear wheels.

Awesome
2009 Shelby Cobra Jet

The package costs $1900 for a nearly 30% horsepower boost, and includes a flowed and ported blower with an overdrive (undersized pulley), throttle body, fresh air kit, and tune.

Dyno testing have shown this package to yield around 554-hp, 520 torque, at the rear wheels!
Find out more at Paul’s HP website.