Dodge SRT Challenger Demon
Dodge wanted to create a Challenger that was even faster and more menacing than the SRT Hellcat, and it succeeded. Here is the Dodge SRT Challenger Demon. It’s an 840 horsepower single seat drag car from the factory that has already been banned by the NHRA because of its quarter mile elapsed time of 9.65 sec at 140 MPH!! Zero to 60 MPH is accomplished in only 2.1 seconds and zero to 100 MPH only takes 5.1 seconds!!! How is that possible?
For starters, all the horsepower is generated by a revamped 6.2L supercharged Hemi, which delivers 808 horsepower and 717lb-ft of torque on premium gasoline (91+ octane) or 840 horsepower at 6,300rpm and 770lb-ft of torque at 4,500rpm when running 100-octane unleaded racing fuel.
The 6.2L Hellcat V8’s 2.4L supercharger has been replaced with a 2.7L version; and boost was raised from 11 pounds to roughly 14.5 psi when running on the 100+ octane race gas (closer to 15 with ideal conditions).
The valve train and rotating assembly of the 2018 Dodge SRT Challenger Demon (crankshaft, connecting rods, pistons) have been strengthened. Otherwise, and not counting the Torque Reserve system, intercooler chiller, and bigger blower, 100-octane tune, and reinforcing various components, the Demon engine isn’t all that different from the Hellcat cars.
With the stock computer system running on premium gasoline (91+) and the huge 315 Nittos up front, the new supercharged Challenger will still lift the front wheels off of the ground on launch and it will still run a 9-second quarter mile — 9.90 to be exact. (The Demon’s Eco mode, which starts the car in second gear and limits power to 500 hp, runs a 11.59 quarter-mile.)
All of that power is sent through the same basic 8-speed automatic transmission as the Hellcat cars, with a higher stall torque convertor and the integrated TransBrake, which works with the Torque Reserve system.
The trans-brake, which essentially “traps” the engine power in the transmission so as they increase engine RPM, there is no power spinning the rear wheels or pushing the front wheels. When the trans-brake is released, all of that power is instantly sent to the rear wheels and the car rockets out of the hole with far more force. The Demon’s computer system even displays the Trans Brake feature for the driver when in use.
The Demon can launch at 2,350 rpm without touching the brakes, while increasing launch boost pressure by 105% and launch torque levels by 120%. This system provides Challenger Demon 40% more torque on launch than trying to launch the car with skinny front tires using only the brakes. It works with the anti-lag system.
The Challenger Demon will also be the first production road car to come with a “torque reserve” system – or what racers commonly call an anti-lag system.
Normally, there is a lag between the time you first hammer the throttle to the time when you reach full boost, because the engine has to rev to build pressure in the supercharger. The torque reserve (or anti-lag) system closes the supercharger bypass valve, so boost pressure rises faster; and the engine computer briefly deactivates alternating cylinders to spin the engine faster, while keeping power output low.
On launch, the Demon will leave the line at a higher engine speed and a higher boost level, a performance edge; and it’s a little easier on the drivetrain components when preparing to launch. A byproduct is a unique exhaust sound — the alternating cylinder deactivation creates a distinctive “stutter.”
When this system is activated, the driver holds down the left shift paddle on the steering wheel, engaging the TransBrake, locking the output shaft – all without touching the brakes. When the driver is ready to launch, they let off the shift paddle and all of the Demon’s power is sent to the rear wheels in roughly 150 milliseconds, quicker than in a car being launched with the two-foot method.
The Demon TransBrake has a unique preloading feature which applies a moderate amount of power to the drivetrain, but not enough to risk spinning the tires or moving the car. That helps protect the driveshaft, the rear differential and the axle shafts, but and also allows the power delivery to happen so quickly.
It is the first ever road-going car equipped with a trans brake, which is built into the 8-speed automatic transmission, allowing it to get away from the line harder and more consistently than when launching strictly with the brakes.
When a Hellcat Challenger launches, it has almost no boost pressure, resulting in around 100 lb-ft of torque to start. On the other hand, the Demon is running around 8.3 pounds of boost and 534 lb-ft of torque at the point of launch – which is how it can rip the front wheels off of the ground. In fact, the Demon launches so hard that it creates around 1.8g of acceleration force on launch.
Many race cars have an electric cooling system to keep the fans on and the coolant moving after the engine is shut off. The 2018 Dodge Challenger SRT Demon has a similar system, but the “After-Run Chiller” pushes air through the intercooler cooling loop; as a result, the Demon will be cooled down and ready for the next run more quickly than, say, the Challenger Hellcat or the Camaro ZL1.
The Demon’s After-Run Chiller is controlled from the infotainment system; it turns itself off when the target temperature is reached, and the driver can monitor the temperatures via the Performance Pages.
The 2018 SRT Challenger Demon Performance Pages also have a real-time horsepower graph, timers for 0-60, 0-100, eighth mile and quarter mile, a G-force meter and a full suite of auxiliary gauges which display everything from boost pressure and intake air temperature to oil pressure and engine horsepower. The system lets the driver set up the Line Lock, Launch Control, and gear-by-gear shift light systems.
The Demon has a much wider and taller scoop at the front of the hood, measuring 45.2 square inches, the biggest on any production car in America. It sends air through a channel in the underside of the Demon’s aluminum hood to a larger air box which, when the hood is closed, does not draw any air from the hot engine bay. This new system is called the Air Grabber.
The Air Grabber name is from B-body cars of the late 1960s and early 1970s, which had a manual control knob; the new system is always open, and lowers the intake air temperature by a whopping 30°F. Cooler air leads to more power. Like the modern Shaker hood, the new Demon Air Grabber with have a unique logo under the hood to go along with the unique air intake setup and the duct in the hood.
The NHRA-certified quarter-mile time of 9.65 at 140 miles per hour is the fastest for any production road car in the world, period, in the quarter mile.
Those numbers were achieved with the skinny front wheels and the high octane race fuel computer.
The skinny front wheels and tires are included in the Track Pack option that will be delivered to you with a hydraulic floor jack, and they can fit into the trunk for quick changes at the drag strip!
The skinny front wheel and tires also reduce front end weight and aerodynamic drag.
The Demon comes from the factory with only one seat, the driver’s seat. This is only one of the weight reduction techniques used to achieve sub 10 second quarter mile times. The Demon is 232 pounds lighter than the Hellcat, and the seats count for almost half of that amount. The passenger seat is optional and can be added to the sticker price for one dollar.
The rear seat can be added as well, and yes, it is priced at only one dollar on the window sticker. But why add all that weight? You just put yourself out of the 9-second club.
How can the Demon be NHRA approved? It’s not legal in NHRA competition as it is delivered new from the factory, due to its sub 10 second elapsed time. A car that quick must have an approved roll bar to be allowed to run at an NHRA track. The Dodge SRT engineers provided a mounting system where an optional four point safety bar can be bolted behind the front seats without any cutting or drilling.
Here’s a video for even more Challenger Demon action and info!