The first copies of the 2013 SRT Viper to reach consumers
    may not arrive until February as the Chrysler Group works to make sure that
    there are no “bugs” in the first batch of production supercars but thanks to
    the folks at Edmunds.com, we get a look at the 2013 SRT Viper GTS on the dyno
    for the first time.  The results are
    right about where we would expect the new Viper to be in terms of wheel
    horsepower with an output of 558 horsepower and 528lb-ft of torque but more
    importantly – these figures put the Viper slightly ahead of the Corvette ZR1 in
    terms of the amount of power available at the wheels.

    The 2013 SRT Viper GTS tested by Edmunds is rated as having
    640 horsepower and 600lb-ft of torque but that number is at the transmission –
    not at the wheels.  Due to the fact that
    the power has to travel from the engine through the transmission, down the
    driveshaft, through the rear differential and along the rear axles en route to
    the asphalt, there is a given amount of power that is lost and that figure is
    referred to as drivetrain loss.  In a
    rear wheel drive car, we generally assume a drivetrain loss of 12-15% so in
    theory, the 640 horsepower Viper should make between 544 and 563 after that unavoidable
    power loss.  The figure of 558 horsepower
    is in the middle of that range and 558 wheel horsepower from 640 horsepower at
    the crankshaft gives the Viper a drivetrain loss rate of just 12.5%.

    I looked around the internet a bit and found that
    CorvetteForum.com, those who have dyno tested their stock Corvette ZR1 have
    seen wheel horsepower numbers in the range of 540-550 horsepower so while it is
    only a small margin – the 2013 Viper seems to have a slight advantage in how
    much power it puts to the road.  Also,
    based on the fact that the Corvette ZR1 offers 638 horsepower at the
    crankshaft, it seems as though the Viper is more efficient in terms of putting
    its available power to the road.

    We are sure to see more test results like this for the 2013
    SRT Viper – especially once the privately owned models begin reaching the hands
    of owners, racers and performance shops around the country as soon as next
    month.  The battle with the Corvette ZR1
    is going to be a tight one and according to Chrysler, fitting the new Viper
    with the right driver will allow the new Mopar supercar to best the top of the
    line Corvette.

    Check out the video below of the 2013 SRT Viper GTS on the
    dyno from the folks at Edmunds and Click here to talk about the 2013 SRT Viper in the Viper section here on DodgeForum.com!