However, and maybe its just how they decided to do the run, that speed pull looks painfully pathetic. My R will get to 100 faster. So they must be slow rolling the shit out of this thing.
Jalopnik reports that's what happened at the Johnny Bohmer Proving Ground in Florida. A Demon owner took their car up to 203 mph on the proving ground's 2.3-mile runway, as verified by Tag Heuer professional-grade timing equipment. The car was equipped with P Zero tires, and was using the Demon Crate PCM, which in addition to removing the speed limiter, allows for the use of 100-octane fuel, unlocking the V8's full 840 hp.
A caveat, though. While 203 mph is quite fast, it's worth noting that Dodge quotes a 199-mph top speed for the regular Challenger SRT Hellcat. So, 137 horsepower nets a gain of 4 mph. This 203-mph run is still impressive though, considering Dodge didn't build the Demon for this sort of thing.