Dodge Reveals More Details on the Demon's Engine

Jason Siu
by Jason Siu

Sixty-two percent of the Demon’s engine is different than the Hellcat.

In April, Dodge finally pulled the cover off the Challenger SRT Demon, revealing an 840-horsepower muscle car set to terrorize the streets. Now, the American automaker has spilled more details on the 6.2-liter supercharged V8 powerplant, including that each Demon and Hellcat engine is dyno tested for 42 minutes under load up to 5,200 rpm before they’re shipped off to the company’s assembly plant in Brampton, Ontario.

As for the Demon’s internals, the block is deck plate honed to minimize bore distortion, while the cylinder heads are machined on dedicated Demon/Hellcat CNC machines. New parts compared to the Hellcat’s V8 include crankshaft, pistons, connecting rods, and supercharger. Dodge says there’s also a 33 percent increase in oiling for the valve springs and rocker tips, while single-groove collets on the valve stems improve stability. To handle the 840 horsepower, fuel injector pressure has been increased 27 percent and both the oil pan and windage tray have been optimized for high acceleration, with the company testing it up to 1.8 g.

To get all the power to the ground, the TorqueFlite 8HP90 eight-speed automatic transmission features an upgraded torque converter that increases torque multiplication 18 percent. The stall speed on the converter has also been increased 11 percent, while in Drag Mode, the transmission minimize torque cut during gear changes thanks to 400-millisecond shifts.

SEE ALSO: Top 10 Things You Need to Know About the 2018 Dodge Demon

But if you’re not into all the technical specifications of the Demon’s V8 engine, Dodge shared some fun facts about the Dodge Challenger SRT Demon. For example, during a quarter-mile run, the Demon ingests 173 cubic feet of air, which is the equivalent to the lung capacity of 816 humans. Meanwhile, 800 feet into a quarter-mile run, the Demon V8 would empty all the car in the cabin of the Challenger SRT Demon – the equivalent of 105 cubic feet.

The engine’s cooling system in the Demon rejects 258 kW of heat at rated power, which would boil 1 quart of water at room temperature in just 1.2 seconds. Dodge says the heat rejected is equal to 250 electric toasters. And if you’re wondering just how well the fuel system performs, at rated power it flows 1.36 gallons of high-octane fuel per minute. To put that into perspective, the typical shower head flows at two gallons per minute.

And to compare the Demon’s engine to the Hellcat’s V8, Dodge said that on each power stroke, the piston and connecting rod are loaded with 11 tons of force, the equivalent of five 2018 Dodge Challenger SRT Demons. This happens more than 50 times a second at 6,300 rpm! Lastly, over one ton (2,500 pounds) is transferred from the front to rear wheels at launch.

Discuss this story on our Dodge Challenger Forum

Jason Siu
Jason Siu

Jason Siu began his career in automotive journalism in 2003 with Modified Magazine, a property previously held by VerticalScope. As the West Coast Editor, he played a pivotal role while also extending his expertise to Modified Luxury & Exotics and Modified Mustangs. Beyond his editorial work, Jason authored two notable Cartech books. His tenure at saw him immersed in the daily news cycle, yet his passion for hands-on evaluation led him to focus on testing and product reviews, offering well-rounded recommendations to AutoGuide readers. Currently, as the Content Director for VerticalScope, Jason spearheads the content strategy for an array of online publications, a role that has him at the helm of ensuring quality and consistency across the board.

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  • Earl Crabb Earl Crabb on Jun 05, 2017

    I wish................I wish they would hand the keys over to one lucky person and it were me.......oh well, too old to be setting bad examples for my daughter. Nice job Dodge!

  • No Mas No Mas on Jun 21, 2017

    id like to know my best option for "refreshing" the 5.2 (318cc) engine in my truck. Balance of power, and response.