Road & Track was recently discussing the frankly insane Dodge Viper ACR and its undeniable track capability with the vehicle development manager for the Viper, Jeff Reece. A one on one with a vehicle development manager will almost always yield interesting conversation, however R&T managed to dig up an especially unique fact about the Viper ACR when talking with Reece.
Reece told R&T that Fiat Chrysler lead designer Ralph Gilles discovered the Viper ACR’s Extreme Aero package not only creates drag when the car is in motion, but also when it’s stationary on the back of an open trailer. In fact, the ACR creates so much drag when being towed, it affected the MPG rating of Gilles Grand Cherokee EcoDiesel he uses to tow the supercar.
“I tow with my EcoDiesel Grand Cherokee, which normally would get 20-21mpg towing my (Viper) GTS, and got 18-19 towing the ACR,” he told R&T when asked for comment on the interesting matter. “I am in the process of fashioning a simple device that stalls the rear wing.”
Peak downforce on the Viper ACR is 1,700 lbs, which is achieved when the car is traveling 177 mph. Gilles’ obviously isn’t travelling anywhere near those speeds when towing his Viper ACR, but the fact the car produces enough down force at 60 mph to negatively affect fuel economy is telling in itself.