Do EVs Need A Passing Gear? Nissan Says Yes, Chevy Disagrees

By Antony Ingram

2,049 views Jul 13, 2010

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One of the benefits of the electric vehicle experience is the near instantaneous torque at your disposal when you prod the right-hand pedal: no shifting, no "kickdown," just smooth power.

So why exactly would the 2011 Nissan Leaf electric car have a "passing gear"?

On any electric car, the torque starts to level out the faster you go. And unlike a conventional geared combustion engine car there are no gears to change down into to increase your torque and power at a particular road speed.

In most situations though, plug-in electric cars like the 2011 Nissan Leaf and 2011 Chevrolet Volt should still have enough urge to pass safely at anything other than very high speeds.

However, Edmund's Inside Line report in a recent test drive that Nissan appears to have equipped the 2011 Leaf with a simulated "passing gear," with an extra reserve of power that's available should you push the accelerator pedal all the way down.

This would be similar to the extra step many automatic transmission cars have to initiate "kickdown".

Confusingly, Nissan North America's product planning and advanced technology director Mark Perry, from whom Edmund's sourced the information, claims that there are "no gears or 'step down'," and that the Nissan Leaf's electric motor "still has sufficient torque to have good passing speed from 55 to 70."

2011 Chevrolet Volt in Waco, Texas, en route during the 1,776-mile Freedom Drive PR stunt

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Whether or not the 2011 Leaf has a simulated boost for passing then seems unclear. It is clear, though, that Chevrolet's 2011 Volt doesn't have anything of the sort, although it may be offered with a "mountain mode" for steep hills.

This could be because Chevrolet have reached the same conclusions that Mark Perry mentions, and that power and torque are sufficient for safe acceleration at higher speeds without needing a boost of some sort.

It's worth also noting though that the 2011 Volt is more powerful than the Nissan, making 110 kilowatts to the Leaf's 80 kw (147 hp versus 107 hp). The Volt's peak power does include the 20 kw (26hp) increase available in the engine's sport mode.

The Leaf offers no sport setting, just standard and Eco power modes. The latter doesn't reduce the actual power, but instead softens the initial pedal response and boosts brake regeneration.

At lower speeds the performance difference probably won't be quite as noticeable, as the Nissan benefits from 400 pounds less weight than the Chevy.

Of course, you'll be paying less money for the car with less performance, too. The Nissan Leaf comes in at around $32,000 with the 2011 Volt expected to start around $40,000, both before federal and local tax incentives are taken into consideration.

Do you think that electric vehicles should have a simulated passing gear? Let us know your thoughts using the comments form below.

[Edmunds via GM-Volt.com]