From Car and Driver:
“Showroom Demons make 808 ponies on premium fuel, an increase of 101 over the Hellcat.
To unlock 840 in the Demon, buyers must also purchase the Demon Crate. Cost is TBD, but Kuniskis hopes it also will cost $1.
In the crate are some skinny front wheels, all the Snap-on tools needed to change tires at the track, a new engine ECU, a new air filter, a low-temperature thermostat, a cover plate to facilitate removing the passenger-side mirror, and a new HVAC switch module with an extra button on it.
That button, a gas-pump silhouette with “HO” in the middle, activates a high-octane engine map (hence the ECU and air filter), upping power to 840 hp and torque to 770 lb-ft at 4500 rpm, up from 717. Kuniskis says the Demon is emissions compliant no matter what mode it’s running.
All the tools and the skinny “runners,” as the skinny wheels are called, fit in a molded piece of foam that fits nicely in the trunk and is easily removed in the paddock.”