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It’s Here! EVERY Detail On The 9-Second Dodge SRT Demon!
http://www.hotrod.com/articles/every-detail-9-second-dodge-srt-demon/
After much secrecy and intrigue the 2018 Dodge SRT Demon is finally unwrapped for all to see. We first picked up the scent in 2014, when rumors of an all-out drag car called “ADR” surfaced. Then in January 2017, we got confirmation that something was afoot. The Dodge PR machine began leaking weekly teasers of a strange and wonderful new performance car called Demon. Animated short videos on Dodge’s IfYouKnowYouKnow.com website gave clues into the car’s purpose and capability, with increasing specificity as the car’s official debut loomed. We quickly learned that the Dodge Demon would be unlike any car ever produced. It would be more powerful, faster, and possessed of a unique skillset that made it the most capable quarter-mile production car ever.
Incredibly, in stock trim the SRT8 Demon can pull both wheels off the ground at launch. That fact alone is so cool, Dodge invited the Guinness Book Of World Records to document the feat as the first factory car ever to do a wheelie. (A length of 2.92 feet in fact.) In the process, the Demon generates 1.8g of acceleration, another record for a production car. At the same test session, Dodge engineers went for yet another record: fastest production car in a quarter mile. With the Demon’s optional race fuel programming (for 100-plus octane unleaded fuel) and optional lightweight front racing wheels, it runs the quarter mile in 9.650 seconds at over 140 mph. Even with all four of its standard Nitto NT05R 315/40R18 drag radials bolted up, the Demon is good for 9.90s at over 130 mph. This kind of performance from a street-legal vehicle was unthinkable a year ago, let alone back in the ’60s. The Demon is so quick, at the same test session the NHRA banned it from competition for infractions of Section 4 in the rule book.
Fortunately, the Demon is not banned for use on the street. All of the Demon’s 808 HP and 717 lb-ft of torque is legal in all 50 states. There will be plenty of them to go around too (production begins late this summer) as Dodge will be building 3,000 of them for the United States and 300 for Canada. Dodge states the Demon’s 0-60mph performance as 2.3 seconds, which at first looks like a misprint, until you realize the kind of acceleration you need to pull off high nines in street dress. Sounds about right—just make sure you eat your Wheaties in the morning so you don’t pass out from the g force!
Under The Hood
There’s a ton of hardcore engineering that went into the Demon to get those numbers, much of it under the hood. A new Air-Grabber induction system includes the largest functional hood scoop (45.2 square inches) of any production car ever. The Air-Grabber hood is sealed to the air box, which is also fed from the driver-side Air-Catcher headlamp and an inlet near the wheel liner. Combined, those sources give the Demon’s 6.2L V8 Hemi an air-flow rate of 1,150 cubic feet per minute, or 18 percent greater than the Hellcat.
A larger 2.7-liter supercharger moves more air, thanks to an increase in boost pressure to 14.5 psi (up from the Hellcat’s 11.6 psi). Max engine speed is also raised from 6,200 (in the Hellcat) to 6,500 rpm. Improving on the Hellcat is a first-ever production car Power Chiller liquid-to-air intercooler chiller system and After-Run Chiller that keeps cooling the supercharger after the engine is shut off. Buyers who opt for the Demon Crate (more on this later) get a specially tuned PCM allowing the Demon to run on 100-plus high-octane unleaded fuel or 91 octane on demand. Power surges to 840 HP and 770 lb-ft on the race tune and Demon now comes with two dual-stage fuel pumps to support that. In addition, the Demon’s Hemi includes a high-speed valvetrain, strengthened connecting rods and pistons, and an improved lubrication system. The upgrades enable the engine to sustain higher output and pressures while meeting stringent durability requirements. We’re told that the Demon Hemi only retains about 50 percent of the Hellcat’s internals, but if past experience is any indication, most of these changes would be minor tweaks (stuff like larger injectors), not huge departures from existing engineering or architecture.
3, 2, 1… Launch!
Getting the Demon to launch hard, launch reliably, and launch consistently time after time, a whole new bag of tricks was employed. For the first time ever (you better get used to that phrase) Dodge turned to age-old racer technology and built a trans brake right into the beefcake TorqueFlight 8HP90 eight-speed automatic—the only trans available in the Demon. Internal changes to the trans include an upgraded torque converter that delivers an 18 percent increase in torque multiplication. Also, the stall speed is increased 11 percent and the lockup speed is increased. The trans brake—recast in corporate-speak as TransBrake—locks the transmission output shaft to hold the car in place before a standing start. It does this by engaging clutches A, B, and C while delivering power to clutches D and E when the trans is in First gear. Locking these clutch sets together lets the driver increase engine speed up to 2,350 rpm without overpowering the brakes, resulting in quicker power delivery and up to 15 percent more torque at launch. Steering wheel paddle shifters trigger the trans brake, improving reaction time by 30 percent compared to a foot-brake launch. The system enables delivery of initial torque to the flywheel as soon as 20 milliseconds after launch.
In concert with the trans brake, the Demon’s Drag Mode Launch Assist uses wheel speed sensors to watch for driveline-damaging wheel hop at launch and in milliseconds modifies the engine torque to regain full grip and then continue accelerating the car down the track. If you look at accompanying video footage of the Demon launching, you can visibly see where the PCM reins in wheelspin—a nifty trick that will produce faster e.t.s and may even save the car from heading toward the wall.
Equally nifty is something Dodge calls Torque Reserve. This acts like an electronic boost controller in a turbo car and becomes active once engine speed passes 950 rpm. The old trick in a footbraked turbo Grand National was to pump up the brake on the line and build as much boost as you could before launching. In the Demon, Torque Reserve closes the bypass valve, prefilling the supercharger with boost, while the PCM manages fuel flow to cylinders and manages spark advance or retard to balance engine rpm and torque.
With the trans brake and Torque Reserve active, the SRT Demon has more than 8 psi of boost at launch and up to 120 percent more engine torque than without Torque Reserve. The trans brake also preloads the driveline with torque, leading to full engine torque delivery at the rear wheels 150 milliseconds after the shift paddle is released. That results in faster acceleration at launch, faster 60-foot times, and an improvement of more than a tenth of a second in quarter-mile times, which computes to an entire car length at the finish line.
.............Lots more at the link..............
http://www.hotrod.com/articles/every-detail-9-second-dodge-srt-demon/
After much secrecy and intrigue the 2018 Dodge SRT Demon is finally unwrapped for all to see. We first picked up the scent in 2014, when rumors of an all-out drag car called “ADR” surfaced. Then in January 2017, we got confirmation that something was afoot. The Dodge PR machine began leaking weekly teasers of a strange and wonderful new performance car called Demon. Animated short videos on Dodge’s IfYouKnowYouKnow.com website gave clues into the car’s purpose and capability, with increasing specificity as the car’s official debut loomed. We quickly learned that the Dodge Demon would be unlike any car ever produced. It would be more powerful, faster, and possessed of a unique skillset that made it the most capable quarter-mile production car ever.
Incredibly, in stock trim the SRT8 Demon can pull both wheels off the ground at launch. That fact alone is so cool, Dodge invited the Guinness Book Of World Records to document the feat as the first factory car ever to do a wheelie. (A length of 2.92 feet in fact.) In the process, the Demon generates 1.8g of acceleration, another record for a production car. At the same test session, Dodge engineers went for yet another record: fastest production car in a quarter mile. With the Demon’s optional race fuel programming (for 100-plus octane unleaded fuel) and optional lightweight front racing wheels, it runs the quarter mile in 9.650 seconds at over 140 mph. Even with all four of its standard Nitto NT05R 315/40R18 drag radials bolted up, the Demon is good for 9.90s at over 130 mph. This kind of performance from a street-legal vehicle was unthinkable a year ago, let alone back in the ’60s. The Demon is so quick, at the same test session the NHRA banned it from competition for infractions of Section 4 in the rule book.
Fortunately, the Demon is not banned for use on the street. All of the Demon’s 808 HP and 717 lb-ft of torque is legal in all 50 states. There will be plenty of them to go around too (production begins late this summer) as Dodge will be building 3,000 of them for the United States and 300 for Canada. Dodge states the Demon’s 0-60mph performance as 2.3 seconds, which at first looks like a misprint, until you realize the kind of acceleration you need to pull off high nines in street dress. Sounds about right—just make sure you eat your Wheaties in the morning so you don’t pass out from the g force!
Under The Hood
There’s a ton of hardcore engineering that went into the Demon to get those numbers, much of it under the hood. A new Air-Grabber induction system includes the largest functional hood scoop (45.2 square inches) of any production car ever. The Air-Grabber hood is sealed to the air box, which is also fed from the driver-side Air-Catcher headlamp and an inlet near the wheel liner. Combined, those sources give the Demon’s 6.2L V8 Hemi an air-flow rate of 1,150 cubic feet per minute, or 18 percent greater than the Hellcat.
A larger 2.7-liter supercharger moves more air, thanks to an increase in boost pressure to 14.5 psi (up from the Hellcat’s 11.6 psi). Max engine speed is also raised from 6,200 (in the Hellcat) to 6,500 rpm. Improving on the Hellcat is a first-ever production car Power Chiller liquid-to-air intercooler chiller system and After-Run Chiller that keeps cooling the supercharger after the engine is shut off. Buyers who opt for the Demon Crate (more on this later) get a specially tuned PCM allowing the Demon to run on 100-plus high-octane unleaded fuel or 91 octane on demand. Power surges to 840 HP and 770 lb-ft on the race tune and Demon now comes with two dual-stage fuel pumps to support that. In addition, the Demon’s Hemi includes a high-speed valvetrain, strengthened connecting rods and pistons, and an improved lubrication system. The upgrades enable the engine to sustain higher output and pressures while meeting stringent durability requirements. We’re told that the Demon Hemi only retains about 50 percent of the Hellcat’s internals, but if past experience is any indication, most of these changes would be minor tweaks (stuff like larger injectors), not huge departures from existing engineering or architecture.
3, 2, 1… Launch!
Getting the Demon to launch hard, launch reliably, and launch consistently time after time, a whole new bag of tricks was employed. For the first time ever (you better get used to that phrase) Dodge turned to age-old racer technology and built a trans brake right into the beefcake TorqueFlight 8HP90 eight-speed automatic—the only trans available in the Demon. Internal changes to the trans include an upgraded torque converter that delivers an 18 percent increase in torque multiplication. Also, the stall speed is increased 11 percent and the lockup speed is increased. The trans brake—recast in corporate-speak as TransBrake—locks the transmission output shaft to hold the car in place before a standing start. It does this by engaging clutches A, B, and C while delivering power to clutches D and E when the trans is in First gear. Locking these clutch sets together lets the driver increase engine speed up to 2,350 rpm without overpowering the brakes, resulting in quicker power delivery and up to 15 percent more torque at launch. Steering wheel paddle shifters trigger the trans brake, improving reaction time by 30 percent compared to a foot-brake launch. The system enables delivery of initial torque to the flywheel as soon as 20 milliseconds after launch.
In concert with the trans brake, the Demon’s Drag Mode Launch Assist uses wheel speed sensors to watch for driveline-damaging wheel hop at launch and in milliseconds modifies the engine torque to regain full grip and then continue accelerating the car down the track. If you look at accompanying video footage of the Demon launching, you can visibly see where the PCM reins in wheelspin—a nifty trick that will produce faster e.t.s and may even save the car from heading toward the wall.
Equally nifty is something Dodge calls Torque Reserve. This acts like an electronic boost controller in a turbo car and becomes active once engine speed passes 950 rpm. The old trick in a footbraked turbo Grand National was to pump up the brake on the line and build as much boost as you could before launching. In the Demon, Torque Reserve closes the bypass valve, prefilling the supercharger with boost, while the PCM manages fuel flow to cylinders and manages spark advance or retard to balance engine rpm and torque.
With the trans brake and Torque Reserve active, the SRT Demon has more than 8 psi of boost at launch and up to 120 percent more engine torque than without Torque Reserve. The trans brake also preloads the driveline with torque, leading to full engine torque delivery at the rear wheels 150 milliseconds after the shift paddle is released. That results in faster acceleration at launch, faster 60-foot times, and an improvement of more than a tenth of a second in quarter-mile times, which computes to an entire car length at the finish line.
.............Lots more at the link..............
