Aggressive Sound. Give your 4.6L 3-valve Mustang an aggressive lopey idle reminiscent of the classic muscle cars of the 60's with a set of Ford Racing Hot Rod Cams. No other cam manufacturer can offer the same aggressive sound and durability of these cams, in fact no one will believe it's a modular engine. Safe Upgrade. These Hot Rod Performance Camshafts were engineered by the same Ford designers of the stock cams to provide the most powerful cams available that are safe with the stock production valve train of your 2005-2010 GT. The Hot Rod Performance Cams are compatible with production springs, followers, and lash adjusters up to 6800rpm. More Power. Ford dyno testing has shown a 50hp gain with a stock intake manifold and CNC heads at 6500 RPM. The same vehicle without the CNC heads, but with long tube headers and cold air kit installed will see an impressive 30hp gain. Required Upgrade. To realize the full power potential that these Ford Racing Hot Rod Performance Camshafts have to offer, AmericanMuscle recommends a custom Bama tune with a Mustang Handheld Tuner to reprogram the vehicles computer (ECU) for proper operation. Application. Designed as an upgrade for the 2005-10 Mustang GT 4.6L 3V engine the Ford Racing Hot Rod Performance Cams require custom calibration to achieve optimized performance.