If the insane McLaren 720S has taught us anything since its premiere more than two years ago, it’s that McLaren has made a habit of understating the horsepower and torque figures of its street cars.

You see, McLaren says that the 720S makes 710 hp at the crank but various dyno results show that it almost makes that much at the rear wheels, meaning engine power likely sits at well over 750 hp. It seems as though McLaren has also understated the figures for its track-focused Senna hypercar.

McLaren claims that the 4.0-liter twin-turbo V8 engine of the Senna pumps out 789 hp and 590 lb-ft (800 Nm) of torque. The crew at Hennessey Performance recently put their black Senna to the test by strapping it onto a dyno and letting it loose. It delivered some seriously impressive figures.

Testing for the hypercar saw it deliver 724 hp at the rear wheels and 627 lb-ft (850 Nm) of torque. Factoring in a 15 per cent drive loss, this rear-wheel horsepower figure indicates that the Senna’s twin-turbo V8 could in fact be pumping out over 830 hp. If the drivetrain loss of the car is 20 per cent, engine horsepower could exceed 860 hp.

Looking at these figures, it shouldn’t come as a surprise to anyone as to why the Senna is as fast as it is yet despite this, Hennessey Performance announced at the start of April that it is working on a number of tuning packages for the Senna. These include one which will churn out at least 1000 hp while another will produce approximately 900 hp.