American Muscle continues the Bolt-On Buildup with 2010-12 Shelby GT500


American Muscle continues the bolt-on build up series with three stages of modifications for the supercharged 2010-12 Shelby GT500’s. As they do with all their vehicles they lay down a baseline dyno run to see how well the vehicle performs with no bolt-on’s. This time their 2012 Shelby GT500 put down 503 horsepower and 475 lb-ft of torque. A very respectable number for a high performance vehicle but lets see how well it responds to some minor bolt-on’s.

The Stage 1 bolt-on’s include a JLT Big Air Cold Air intake system and a Bama X4/SF4 Power Flash tune. These mods were good for an increase of 31 horsepower and 28 lb-ft of torque. Not bad considering no major installations were done.

The Stage 2 bolt-on’s included a Metco Motorsports supercharger pulley (2.6″), NGK V-Power Spark Plugs and a Metco Motorsports Auxiliary Pulley Kit. These three mods are significantly cheaper in price than the stage 1 mods so we are eager to see how they perform. These mods were good for an increase of 32 horsepower and 36 lb-ft or torque. As you can see their are some basic mods which will net you some serious horspeower and all three of these can be purchased for under $500.

For Stage 3 American Muscle gets serious as they add a Ford Racing Twin 65mm Cobra Jet Throttle Body, Magnaflow exhaust system, Gates 10-rib serpentine belt, Innovators West 10% Overdrive Harmonic balancer pulley and an AFCO Pro-Series Heat Exchanger with fans. These mods are by far the most expensive with a ballpark figure of $3,500. These mods were good for 65 horsepower and 83 lb-ft of torque.

Overall the 2012 Shelby GT500 with its three stages added 117 horsepower and 135 lb-ft of torque which are some very impressive numbers for minor bolt-on modifications.

For more on this bolt-on buildup check out the videos below or head on over to their build up page.

All of these bolt-on performance mods are available at

Stage 1 Bolt-On’s:

Stage 2 Bolt-On’s: