One number changes everything: pushing top speed from 274 to over 320 km/h raises the estimated aerodynamic load by roughly 38 percent. That's why the Hennessey Maximus isn't really a horsepower story anymore — it's a fight against the air. The 1,032-hp Ram needs a reworked body just to survive speeds the stock Rumble Bee SRT was never built for.
The factory Ram 1500 Rumble Bee SRT runs a supercharged 6.2-liter HEMI V8 rated at 777 hp and 922 Nm of torque. Ram claims 0-60 mph in 3.4 seconds, the quarter mile in 11.6 seconds, and a top speed target of 170 mph — about 274 km/h.
Hennessey's Maximus program pushes that to 1,032 hp and 1,284 Nm — almost 33 percent more than the factory SRT. The build adds a larger 2.8-liter supercharger, a bigger intake and a more capable intercooler.
Hennessey's claimed numbers land around 3.0 seconds to 60 mph and a 10.9-second quarter mile — 0.7 seconds quicker than the factory Rumble Bee SRT. These are still projected figures, not results from independent testing.
The most telling part of the build sits on the outside. Maximus gets a front splitter, Venom Aero side skirts, a large rear wing and a retractable tonneau cover. The wing is removable specifically for top-speed attempts.
Ram's own numbers explain why. At 170 mph, the automaker says more than 1,000 lbs of aerodynamic force hits the front of a stock Rumble Bee, while the factory aero package only generates 192 lbs of downforce. Push from 170 to 200 mph and, with the same aero, dynamic pressure jumps roughly 1.38 times. That's why crossing 320 km/h demands work on more than just the engine — body stability has to keep up too.
There's a historical benchmark here too. Ram itself compares the new Rumble Bee SRT to the 2006 Dodge Ram SRT-10: 777 hp versus 500 hp, 3.4 versus 4.9 seconds to 60 mph, 170 mph versus 154 mph top speed. That was a record back then. Maximus is meant to make the next leap — past the 200-mph mark.
Hennessey is showing the pre-production truck on August 8 at Roadkill Nights in Michigan — organizers have confirmed the event is happening that day. Production is targeted for the first quarter of 2027, according to the source information.
Three numbers still stand between this project and the finish line: verified top speed, final performance figures and price. Cost and production numbers for the Maximus haven't been announced.
