• Jan 21st 2009 at 10:00AM
  • 33
Click above for a gallery of the Dodge Viper ACR

There's really only one way to get an accurate measure of a car's horsepower, and that's by strapping it on a proper dyno. Even then, not all dyno's produce the same results, but in our numbers-driven society, we'll take what we can get. Two of the fiercest 'Ring competitors are the new Corvette ZR1 and the Dodge Viper ACR, which currently holds the unofficial fastest lap record with a blistering time of 7:22.1. Wondering how they stack up power-wise? According to reports on DragTimes, the duo are pretty darn close with the naturally-aspirated Dodge posting an impressive 546 horsepower and 510 lb-ft of torque compared to the supercharged ZR1's 549.9 horsepower and 500 lb-ft.

Considering that both vehicles use a six-speed stick and power the rear wheels, drivetrain losses should be similar, so these figures are relatively comparable and they prove once again that the horsepower wars are alive and well. For what it's worth, Dodge officially (under) rates the ACR at 600 horsepower, and an estimated 15% loss through the drivetrain would put this beast at an actual 642 horses. Thanks for the tip, FikseGTS!

[Source: DragTimes.com]

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    • 1 Second Ago
      • 6 Years Ago
      how is it possible that this car beat cars that cost 10 times what it costs on the 'ring? somebody explain that to me
        • 6 Years Ago
        • 6 Years Ago

        QFT. Ever ride in one, Cort? It's an exhilarating (and not-mildly terrifying) experience. I haven't ridden in this generation, but a good friend had a GTS ACR ('00, I believe) and it rattled, shook, got hot, etc.

        As close to a real race-car as you're going to get for the streets, with all the associated negatives. I love 'em, but this could only *ever* be a weekend/track car. DD'ing a Viper would be painful.
        • 6 Years Ago
        Interior design. It's that simple. I'd take the go fast car with a less expensive interior myself, but that's just me.
        • 6 Years Ago
        @ Cort
        Dude the Viper is pretty much a street legal race car, the ZR1 'Vette is much more of a GT car. This has a stiff race car suspension, tires, aerodynamics and a 8.4L V10 making close to 650hp and 600ft-lb torque... plus the car is like 3,200lbs. All numbers point towards it being the fastest around the track, and it is.
        • 6 Years Ago
        That's easy: less (than standard) weight, loads of power & torque, adjustable suspension properly dialed in, adjustable aero properly dialed in and R Compound tires. Dodge weren't messing around when they developed the ACR. It really is basically a race car you can drive on the street. I think it's pure bad-ass.
      • 6 Years Ago
      Not a popular view but I would take this over the Vette.
        • 6 Years Ago
        I've ridden in a friend's Viper (which I thought was badass) but I own a Vette as a daily driver.

        After comparing the two side-by-side within minutes of each other....Performance is pretty close depending on the year and model of the cars.....the Viper wins on looks.....but the Vette destroys the Viper in comfort.

        I'm convinced that you can cook eggs on the floor in the Viper because of the way the exhaust is set up. It also rides like a truck.

        The Viper is a racecar that you can drive on the street........where the Vette is a streetcar that you can drive on the track.

        ...on a side-note.....the #8 piston on his Viper just broke....and he babies this car with a whopping 7,000 miles on it......it's in the shop for a few weeks. I told my buddy he should have bought a Vette. ;-)
        • 6 Years Ago
        Agreed, I like the Vettes, especially the Z06. But I'd rather have a Viper. You don't see Vipers every day.
        • 6 Years Ago
        for an everyday car id take a corvette but for something exotic and unique the iper wins everytime
        ive seen so many covettes in my area but only about 3 vipers
        its much more special to see one of those
      • 6 Years Ago
      I love the styling of the Viper, especially in ACR form. It just screams, "Don't mess with me!" The ZR1 is nice too, between the two of them America should be proud.

      On a side note, I remember when MotorTrend dyno'd a Z06, a 2006 Viper, and a Ford GT. The Vette and Viper both dyno'd more than advertised, but the GT dyno'd at a sick 535hp at the wheels! It's nice to see that all of the D3 provide more than they advertise when building these super high performance cars.
      • 6 Years Ago
      Shouldn't the HP numbers in the first paragraph be 646 for the viper and 649.9 for the ZR1?? I know for a fact that the LS9 makes alot more power than 549.
      • 6 Years Ago
      Kinda pathetic that Dodge couldn't give more horsepower from 8.4L.

      Having said that, I'd take both cars. The ZR-1 for my daily driver, and the Viper for weekend fun.
        • 6 Years Ago
        I meant naturally aspirated. But yeah force induction will fix everything powerwise.
        • 6 Years Ago
        Not Couldn't; didn't.
        I know RSI offers 1500 hp twin turbo kits for the viper.
      • 6 Years Ago
      My choice is obvious.
      • 6 Years Ago
      Viper > ZR-1
      • 6 Years Ago
      Dodge has always underrated their performance cars. The Neon SRT4 is a perfect example. It was rated at 230 hp and 250ftlbs yet it made 220ish whp.
        • 6 Years Ago
        Underrated and under appreciated. I'm sick of all the Corvette boys yelling and screaming about their car; the ACR is king!
      • 6 Years Ago
      thosedarnkids, the point is that the ACR and ZR1 are putting down the same power to the ground.... Chevy says the ZR1 has 638HP, this is verified by current standards, so it's making at least that amount of power. The loss is about 14-15% in the ZR1's case.

      Dodge says the ACR has 600HP, obviously this isn't the case, it's more like 640HP like the ZR1. I think the ZR1 and ACR have the same base transmission.

      • 6 Years Ago
      there's a Viper in my town that is UNHOLY!
      It's sooo loud too, every time I see him
      I get goose bumps. I can never get close
      enough to see if it's an ACR.

      for the vette drivers I also had my doors
      blown off by a local 427 Z06.... a memorable day
      but that Viper.... yikes!
      • 6 Years Ago

      Great car. Prefer it to the GT-R which is also a great car.
        • 6 Years Ago
        I'd take the GTR for more of a "daily" but if I wanted a car that just f'n fun, GTR would be nowhere on the list. IDK if I'd get the ACR but I'm sure it sounds like sex and I respect it immensely
      • 6 Years Ago
      The car just looks evil.

      You gotta love a car that beat the ZR-1 twice. It didn't even need to show up a second time to do it.

      I wish they could take it out there and get the sub 7:20 pass it's capable of.
        • 6 Years Ago
        i think this is what the Devil drives

        all I want to do is step on the pedal
        with this car, you don't even need curves to get scares $hittle$$
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