Hennessey’s Supercharged Shelby Mustang GT350 R Rear Wheel HP Dyno Testing August 8, 2017 cars-power Video John Hennessey’s Shelby GT350R Mustang testing on the dyno with it’s HPE850 Supercharged upgrade. Power increase running on Shell V-Power 93 octane fuel: 311 rear wheel HP and 193 rear wheel lb-ft Torque. Source: Hennessey Performance