Hennessey's Dark Horse Pushes the Needle to 7.5k RPM on the Dyno; Guess How Much It Makes?

Three more months passed, and Hennessey stepped up and publicized its intentions of creating an even wilder pony, the H850, with 850 hp (go figure). Unlike Shelby, however, the Texas tuner fiddled with a Dark Horse as a building block. The Vegas-based House of Burnouts took the Mustang S650. It fitted a supercharger to obtain the most radical Super Snake ever.

Hennessey announced its plans for the Dark Horse around the same time Shelby began production of the Super Snake in mid-July last year. Now, Texas is putting the all-new H850 on the dynamometer to show everyone what their creation is really all about. The tuner stated a 70% jump in power, from the 500-hp figure issued by Ford Motor Company to an 850-hp summit.

The Dark Horse squeezes 418 lb-ft from the naturally aspirated 5.0-liter V8. That’s 507 PS and 567 Nm – quite a lot for the Mustang’s rear wheels. Not a lot enough since Hennessey thought that 850 hp and 650 lb-ft would do the car more justice. 862 PS and 881 Nm are sufficient to give supercars nightmares, but that’s not the end of things – not in Texas.

The good folks over in Sealy, Texas, have a very good habit of showing solid proof of their actions, and this can be done in two very simple and straightforward ways. One would be to get the car on the track and have it go against the clock in whatever challenge would be most fitting to prove the tuner’s efforts worth.

The second, more data-centric approach involves putting a prepped car through an output measurement test. Hennessey prefers both in equal measure but ensures that every model they build gets a leg-stretching session on the DynaJet dyno. The Dark Horse H850 has been in the books for such treatment since it was announced, and here it is.

The base 2024 Ford Mustang S650 Dark Horse puts down a measured 427.61 hp and 379.08 lb-ft (433.54 PS and 513.96 Nm) at the rear tires. The H850 sports a 3.0-liter Whipple supercharger that benefits from the tuner’s high-flow air induction system, upgraded fuel injectors, and a new fuel pump. With these add-ons, the Hennessey Dark Horse gets even more grim, delivering a staggering 712 hp at 7,490 RPM and 569 lb-ft at 4,700 RPM at the wheels. In metric, those numbers translate into 722 PS and 772 Nm, and I’m beginning to wonder if this is all that can be obtained from a 5.0-liter V8 Coyote.