By Patrick Rall
The new SRT Viper American Club Racer (ACR) is expected to arrive during the 2014 calendar year and while it will likely have some serious high performance road tires when it arrives – it may not have the significant level of upgrades that many Mopar enthusiasts are expecting as the Street and Racing Technology team has had some limitations handed down from Fiat on the new Viper.
The reason for Fiat limited the level of performance of the SRT Viper ACR?
They don’t want it to outperform the Ferrari F12 Berlinetta.
According to Motor Trend, the SRT engineering team has been told that the 2014 (or 2015) SRT Viper ACR cannot have more power than the Ferrari F12 Berlinetta nor can it have a better power to weight ratio than the F12. This means that the Viper ACR cannot have more than 731 horsepower tucked under the hood nor can it offer a power to dry weight ratio better than 4.7 pounds per horsepower. Many Mopar lovers are upset about this set of limitations but luckily, there is still plenty of room for the Viper ACR to improve over the Viper GTS without stepping on the toes of their Italian cousins.
Realistically, the cap of 731 horsepower really shouldn’t have any impact on the 2014 SRT Viper ACR as the previous Dodge Viper SRT10 ACR did not offer any power improvements over stock. Should the new ACR follow that trend, the 2014/2015 American Club Racer Viper will offer the same 640 horsepower as the 2013 Viper and Viper GTS. Chrysler engineers have commented that the revised 8.4L Viper V10 will easily make way more than 640hp but if the new ACR follows the trend of those which came before it – the power output won’t be anywhere near that of the Ferrari F12 Berlinetta.
Where the rumored limitations set forth by Fiat could come into play is in the power to weight ratio of the next SRT Viper ACR. We can expect that the new ACR will feature many of the same features as past examples which will likely include a higher performance braking system possibly with carbon ceramic rotors, a full suspension overhaul including adjustable dampers, stiffer springs, stiffer anti roll bars and high performance bushings from front to back, aero bits including a large rear spoiler and a front splitter that will combine to improve high speed downforce and a handful of weight reducing items inside and out that will bring the total weight of the Viper ACR down to a more track friendly figure.
One place where the 2014 SRT Viper ACR can reduce weight compared to the Viper GTS is the high tech adjustable suspension system. While this setup is ideal for allowing the Viper GTS to offer a comfortable ride and a stiff, high performance ride, it adds quite a bit of weight to the base Viper. Because of that and the fact that the ACR doesn’t need to ride like a dream, I would guess that the Viper ACR will have a traditional suspension setup although like the previous generation ACR that set records all over the world – the new ACR will have adjustable measures for at-track tuning.
However, with a limit on the power to weight ratio, just how much can SRT bring down the dry weight?
Since the Viper ACR will be based more closely on the base 2013 SRT Viper, we can expect that it will weigh somewhere south of the 3,143 dry weight of the base model with the Track Package. That weight figure amounts to a power to weight ratio of 4.91 pounds per horsepower provided that the ACR has 640 horsepower. If the SRT team is to stay above the 4.7 power to weight figure of the Ferrari F12, they could cut the weight down by 128 pounds (for a dry weight of 3,015 pounds) and still be mathematically worse than the F12.
Fortunately, if the 2014 SRT Viper ACR features tires that are equal to those found on the Chevrolet Corvette ZR1, a new track tuned suspension system, a set of lightweight wheels, a revamped braking package and a dry weight of 3,015 pounds – it will almost certainly be able to beat down the ZR1 while either preserving or reclaiming the many records set by the 2010 Viper ACR.