Hennessey Performance just posted a new video of the HPE1200 Dodge Demon upgrade just before sending it off to a very lucky customer.

The HPE1200 remains a mystery for us here at HotCars. We know what goes into making the HPE1000, which is all very straightforward. The Demon retains its 6.2-L supercharged HEMI V8 but boosts the power from 880 horses to well over 1,000--1,035 hp, to be exact.

As is almost always the case, power is increased by tossing the old 2.7-L OEM supercharger and giving it a shiny new Hennessey 4.5-L supercharger. Then they replace the headers, fuel pump, catalytic converters, supercharger pulley, and throttle body with bespoke, upgraded versions that won’t immediately explode an additional 150 horses running through them.

On the HPE1000, zero to sixty is done in just 1.9 seconds. A quarter-mile is done in just 9.18 seconds at a blistering 152 mph.

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But that’s all when the Demon just has a measly 1,035 hp. There’s very little about the HPE1200 that we can say definitively because Hennessey simply hasn’t posted that data.

On their most recent video, we get a glimpse of just what 1,200-ish horsepower can do. At 0:57 into the video, the Demon punches it all the way from 64 mph to 148 mph by the time the video reaches 1:05. That’s just 8 seconds and puts the Demon well into hypercar territory for acceleration.

But how do they do it? Nobody knows. Is it an even larger supercharger? A brand new engine? A set of unobtanium-based engine headers? Whatever it is, Hennessey isn’t saying.

We do know from a previous video than the HPE1200 makes about 1,013 hp at the rear wheels on the dyno. If we assume that the naming convention holds and the HPE1200 does indeed get around 1,200 hp at the crank, then that’s an efficiency loss of about 15%.

Nobody ever accused Hennessey of making efficient vehicles.

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