The 2021 Ram 1500 TRX boasts a factory-quoted 702 hp and 650 lb-ft of torque, but that's as measured at the crank, not the wheels. Hennessey Performance Engineering tried to measure how much power the TRX makes at the wheels by strapping one to a dyno, but only ran numbers for the rear wheels.
The dyno test showed 538 hp and 570 lb-ft of torque at the rear wheels. That represents around 17% driveline loss, which isn't unusal for a pickup truck. Hennessey previously recorded 20% driveline loss at the rear wheels when it tested a 2019 Ford F-150 Raptor.
The TRX is full-time four-wheel drive, so you might be wondering how Hennessey got dyno results for the rear wheels only. Company founder John Hennessey told Motor Authority that four-wheel drive was temporarily disabled by disconnecting the front driveshaft.
2021 Hennessey Mammoth 1000 1500 TRX
While the TRX was designed for off-roading, the amount of power produced by its 6.2-liter supercharged Hellcat V-8 makes this truck pretty quick on pavement. Ram says it will do 0-60 mph in 4.5 seconds.
Inevitably, that wasn't enough for Hennessey. The company has developed more powerful versions of every Hellcat-powered vehicle, and it's doing the same with the TRX. Dubbed the Mammoth 1000, Hennessey claims its take on the TRX will boast 1,000 hp, will do 0-60 mph in 3.2 seconds, and run the quarter mile in 11.4 seconds.
To achieve those numbers, Hennessey plans to equip the Mammoth 1000 with an upgraded supercharger, pulley, and air intake, stainless-steel headers, high-flow exhaust piping (retaining the catalytic converter), and new engine mapping. The price for the complete truck is $135,350, and Hennessey only plans to build 200 this year.