How serious is Dodge about the Challenger SRT Demon's drag strip performance? Today, the automaker announced that the super-Challenger will be the first production car ever equipped with a transmission brake. Here's what that means, and why it's kick-ass news for drag racers.
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Everything we know about the 2018 Challenger SRT Demon paints it as the ultimate street-legal drag racer, and today's announcement only furthers the evidence. A trans brake is an aftermarket electronic device that locks up an automatic transmission by engaging Drive and Reverse simultaneously. During a drag race, this allows the driver to rev up the engine at the starting line without worrying about the car creeping forward. While the driver waits for the green starting light, he or she can rev the engine to the ideal launch RPM, loading up the car's torque converter and making the car strain mightily against its locked-up transmission.
When the light goes green, the driver releases the trans brake (usually by letting go of a button or switch that kept the trans brake engaged) and the car leaps violently off the line. You can find all kinds of demonstrations of this all over YouTube. Here's an Aussie from Haltech explaining how it works:
A trans brake differs from line lock, a mode where the car engages only the front brakes to allow for a stationary burnout to warm up the rear tires. It's also different from launch mode, where a launch-specific rev limiter lets the driver hold the engine at a specific RPM for launch. They all work in concert at the drag strip: Line lock lets you warm the tires with a burnout as you approach the starting line, launch mode lets you select the right launch RPM, and the trans brake lets you sit at the starting line with the engine revving at that RPM without having to hold the car back with the brake pedal. Naturally, the Demon has all three.
In the Challenger SRT Demon, the trans brake is built right into the factory automatic transmission. It's engaged by the driver pulling on one of the paddle shifters (after navigating through some menus to enable Race mode and Launch mode, we're sure), then released when the light goes green by the driver letting go of the paddle. Dodge says the factory trans brake lets the driver rev up to 2350 RPM at the starting line without having to use the brakes to hold the car, and increases supercharger boost pressure by 105 percent and launch torque by 120 percent at launch.
In addition, the Demon's trans brake preloads the driveline, putting torque on the transmission, driveshaft, rear differential and rear half-shafts when the car is stationary to lessen the shock when the trans brake is released. Still, we have to imagine that the torque from that revving supercharged V8 will put a mighty smack through the drivetrain when the trans brake is released.
Like most of the Demon-specific equipment we've heard about so far, the trans brake is evidence that Dodge intends this car for hardcore drag racers only. It's serious equipment, far more than you need to play around on the street. And it's just another example proving that the Dodge Challenger SRT Demon will be a monster on the strip.
Wanna know everything else that's going into the Demon? Check out our master post of everything we think we know.