We didn't expect the Chevrolet Volt to show up at a recent track day, By Antuan Goodwin, CNET - There are cars that were born for the track and those that have absolutely no business there. The 2011 Chevrolet Volt is one of the latter. But when given the opportunity to lap Mazda Raceway Laguna Seca in GM's newest electrified vehicle, we jumped at the opportunity.
Imagine, for a moment, pushing your favorite dull midsize sedan (say a Toyota Camry or Chevy Malibu) at 8/10ths around your favorite back road with all of the understeer, body roll, and middling power-to-weight ratio. It's unoffensive, but few would call the experience "fun". This is the starting point of the Volt's performance. From this starting point, the Volt's unique power train adds and removes a few characteristics that set it apart from more-traditional vehicles.
For starters, there's no engine noise -- or rather, very little of it. As the first journalist of the day to take the Volt for a fast lap, I was able to experience the car with a mostly charged battery -- the EV arrived at the track with just over half of its batter meter full. Consequently, my maps were done with no noticeable intervention by the Volt's gasoline engine. Wind and road noise were all that could be heard, drowning out the whine of the electric motor. Occasionally, the relative silence would be punctuated by the song of the tires as they touched the paint that marked the track's edges and our apexes. However, the Volt manages to sound different even in that respect. Rather than the ragged screeching that is the rallying cry of hooligans the world over, the Volt's low-rolling resistance tires whistled against the smooth pavement and through the turns. It was almost a beautiful sound.
The lack of engine noise -- combined with the lack of an analog speedometer that could be watched with our peripheral vision -- made it a bit difficult to gauge how quickly we were going as we piloted the EV around the course. This led to our entering the first few fast turns going a bit faster than we should have. Fortunately, the Volt chassis' limits were a bit higher than the power train's, so we managed to keep the electric sedan on the track. The Chevrolet representative in the passenger seat didn't seem to object to our manhandling of those first few turns, but we decided to take the next few bends, including the infamous Corkscrew and the hard left-hander into the front straight, with decidedly less gusto. Our lap was run in the transmission's "L" for low-gearing setting which, according to the GM representative on hand, would allow the Volt to take better advantage of its engine braking and energy regeneration.
Sound wasn't the only thing that was different about the Volt racing experience. Although we were selecting the "low gear" of the Volt's transmission, its gearbox features a single speed. On the road (and on the track) that means that the Volt never has to shift a cog. This alleviates the odd gear hunting that typically plagues conventional manual transmissions and CVTs. As a result, the Volt never pulled a poorly timed midturn shift that would upset the vehicle's balance and was always in the right gear as we entered and exited turns to take advantage of its flat electric torque curve. Blasting up Mazda Raceway's front straight, we were able to get a good feel for the electric acceleration offered by the Volt. Freed from the need to shift, the electric motor provided a gentle but firm push toward its top speed of 100 mph. We never reached that speed; instead we topped out at about 85 mph before having to brake hard and dive into turn 2, the 180-degree Andretti Hairpin.
But don't go getting carried away with fantasies of the Volt being some sort of four-door electric hot rod a la the Tesla Roadster S. While the sedan didn't get out of sorts during our laps around Laguna Seca, it didn't exactly thrill, either. Understeer, that old friend of the safe and predictable production car, was present in a major way, which is to be expected. Also present was a bit of body roll, although not in the quantities that we expected, thanks to the Volt's T-shaped battery pack lowering the vehicle's center of gravity.
With our laps wrapped up, we pulled the Volt back into the paddock and shut it down with a tap of the power button (much like you would with a laptop or other electronic device). As the Volt's LCD displays began to shut down, a trip summary screen informed us that we'd averaged 250+ mpg for our session. Of course, our 4.5 miles of track time fell well within the Volt's estimated 35 miles of full-electric range, even with our pushing it much harder than an EPA would have. Although the vehicle's range extender gasoline engine would have allowed, ideally, the sedan to run laps around the track all day, we noticed that by lunchtime, the white Volt we'd driven had been pulled from the vehicle pool. One could assume that after two or three sessions, we lead-footed journalists had exhausted the Volt's battery, but a racetrack severely tests limits of even high-performing production cars, so there are dozens of potential reasons for the Volt's absence during the afternoon session. (Even BMW's reps kept a careful eye on their precious 335is' brakes between sessions and periodically pulled the sports sedan from the rotation to allow the rotors to cool.)
The fact that Chevrolet even brought the Volt to the track in the first place is a strong indicator of the weight that the automaker is putting behind the electrified vehicle's performance. Although our laps in the GM's car of the future didn't exactly whet our appetite for electric racing, we are convinced that it will be able to handle just about whatever public roads will throw at it and just a bit more excited to spend more time behind the wheel of the Chevrolet Volt.
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