Dodge's newest incarnation of the iconic Viper, called the ACR might just possibly be the ultimate American street legal road racer.
The standard version of the Viper is already pretty out there with regards to design and boldness and no-one can ever say it's not a car that doesn't immediately attract attention wherever it goes, but Dodge has managed to make it even more extreme with this barely street legal track version. The Viper ACR gets completely overhauled suspension and aerodynamics, and just about everything performance-oriented has been upgraded for improved lap times. The engine was left untouched, not that it's a slouch, pushing out 646bhp and 813Nm from its hand-built V10.
The new ACR model was improved in three main areas: aerodynamics, chassis and tyres. On the aero front, the new Extreme Aero package results in a car with “the highest aerodynamic downforce of any production car”, which Dodge claims equates to nearly one tonne of downforce at its 177mph top speed.
For starters, you get that enormous, larger than life, dual element rear wing. It has a unique lip, end-plates, and sits taller and further rearwards, contributing to the fact it produces three times the downforce of the Time Attack model. Other new aero parts contributing to that figure include a rear carbon fibre diffuser, SRT bonnet with removable louvres, detachable extension for the front splitter and four dive planes.
The rear diffuser has removable strakes, which are designed to rub against the track surface at high speeds to increase straight line stabiliy, while the removable bonnet louvres reduce air pressure in the front wheel wells to provide additional downforce. Serious technology is quite abundant here.
On the suspension side of things, aluminium-bodied, double-adjustable coilover Bilstein race shocks are used, which have been specifically designed for the Viper ACR. Overall, the suspension package allows for more than three inches of ride height adjustment, and is more than twice as stiff as the Viper TA. The ACR gets 1.4 degrees more negative camber than the entry SRT model as well.
The tyres are Kumho Ecsta V720 track day items, with unique tread patterns that Dodge claims provide lap time gains even over track-only rubber. Behind the 19-inch alloy wheels sit new Brembo Carbon Ceramic Matrix brakes, which bleed faster while also weighing less than the parts they replace.
While the handcrafted V10 engine is largely untouched, ACR-specific exhaust tips have been fitted to the side-mounted exhaust pipes to provide reduced back pressure. Despite its remit of ripping chunks out of lap times, the Viper resists the urge to go auto, instead keeping the Tremec TR6060 six-speed manual, evidently a real drivers car.
The standard Viper is already a handful, but this monster just takes things up another few notches. Can you say extreme?