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Print 76 comment(s) - last by XtremeM3.. on Oct 20 at 3:04 AM


Eight 2011 Chevy Volts took the 1200-mile roadtrip.  (Source: Jeffrey Sauger for General Motors)
The Volt is withstanding the rigors of road testing admirably

The first preproduction models of the 2011 Chevy Volt hybrid electric plug-in vehicle were built earlier this year.  Since then, the vehicle has been put through a number of rigorous tests.  Starting yesterday, a fleet of eight Volts launched on the most ambitious test of the vehicle to date: a 1,200 mile road trip.

Chevrolet Volt chief engineer Andrew Farah is among those making the round trip from the Milford Proving Ground through Ohio, Pennsylvania, Maryland, West Virginia, before returning home.  The drive will take a few days and will require approximately 4 tanks of gas.

The drive is dubbed the "65-Percent Drive" according to Autoblog, which in GM-speak means the test drive made when 65 percent of the vehicle's hardware and software is done.  Reportedly, GM is actually about 90 percent done, but is just sticking to its traditional naming.  GM will complete 70, 80, 90 and 100 percent drives in coming months.

One thing GM is still tweaking is how much power from the gas-engine generator to put directly to the electric drive motor, versus using the generator power to charge the batteries.  GM is finding that frequently putting the power directly to the motor improves performance.  However, the generator will still charge the batteries in some cases, as well.

The engine will be run between 1,200 and 4,000 rpm, using factors like speed and power load requirements to decide on the necessary speed.  GM wants to keep the engine between 30 to 100 percent load, as higher loads reduce pumping losses.  GM was tight lipped about fuel economy under the old method (sustained charge) or the new method (variable speed, some power going directly to the electric motor). 

The company did say that the prototypes are getting good mileage -- over 300 miles on a tank of gas -- when operating in generator mode.  This is in addition to the vehicle's 40 mile all-electric range.  Another interesting test will be when GM runs the car's gas engine on E85 ethanol fuel.  The vehicles are FlexFuel designs, so they can enjoy both gas and ethanol.

As to the battery mode, the batteries are performing well and aren't getting too cold or too hot, both conditions which can degrade performance.  The cars aren't yet reaching the 40 mile target on a charge, but GM expects to pass that milestone on the next test, with tweaking.  On the trip, GM is testing vehicles both running on a depleted battery charge, and a full charge.

GM is also looking to fine tune and minimize noise, vibration, and harshness (NVH).  Currently, the gas engine typically won't turn on until the car is moving, at which point the noise will be drowned out by the wind and road noises.  GM, nonetheless, is pleased with the performance, and plans to further reduce NVH by tweaking vehicle parameters that effect the road and wind noise.

Other GM engineers were off testing Volts at Pikes Peak in Colorado.  One key concern is whether the Volt will reach a "tipping point", where the gas engine can't sustain battery charging, and the battery becomes depleted below the typical minimum of 30 percent charge.  Even a strenuous 14-mile trip to the 14,000-foot summit was unable to overwhelm the 100 hp generator, though, so it appears that the "tipping point" will never be reached in real world situations  -- if GM's claims hold true.

A critical test to come will be how the vehicle performs in cold weather.  In cold weather, the Volt starts with the generator running, to help heat up vehicle and jump-start performance.  Battery performance typically suffers incrementally worse degradation, the colder it gets (this is a major argument for ultracapacitors which perform favorably, but are more expensive).



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Not bad
By judasmachine on 10/16/2009 9:35:09 AM , Rating: 4
Looks better than a Cobalt.

Anyone else notice the pervy UPS driver?




RE: Not bad
By SiliconJon on 10/16/2009 10:20:57 AM , Rating: 3
Pervy? I can't make out what's on his sign. What does it say, what does it say!


RE: Not bad
By SiliconJon on 10/16/2009 10:24:00 AM , Rating: 2
Nevermind...zoom, learn to use it Jon. "Hey (or Hi) Good Lookin"

So is he referring the fella driving the Volt?


RE: Not bad
By mmcdonalataocdotgov on 10/16/2009 11:29:29 AM , Rating: 1
The sign says "14ct Gold" and then something else.


RE: Not bad
By mmcdonalataocdotgov on 10/16/2009 11:30:49 AM , Rating: 2
I wonder if he gets canned for the canned come on sign.


RE: Not bad
By Camikazi on 10/16/2009 7:01:10 PM , Rating: 3
Don't know much about UPS Union huh? It takes A LOT more then just that to even come close to getting fired, especially a feeder driver. Those guys driving those trucks usually have 20+ years working in UPS and aren't going anywhere.


RE: Not bad
By Davelo on 10/16/2009 12:34:21 PM , Rating: 3
It says "Hi Good Lookin". I think he's trying to score some action on the road.


RE: Not bad
By Jeffk464 on 10/16/2009 11:21:30 PM , Rating: 2
common guys, that was setup and referring to the car.


RE: Not bad
By Aeonic on 10/16/2009 10:32:52 AM , Rating: 5
Nice find, I would have never noticed.

If you ask me, the guy should have his eyes on the road and worry about the family broke down on the shoulder that he's about to kill rather than hamming it up for the camera.


RE: Not bad
By 91TTZ on 10/16/09, Rating: -1
RE: Not bad
By 67STANG on 10/16/09, Rating: -1
RE: Not bad
By lostvyking on 10/16/2009 12:27:19 PM , Rating: 4
I have a 2009 Cobalt (2-door, 2.2 ltr./4cyl/manual transmission)...Columbus Day weekend I got 517 miles on a single 13 gallon tank of gas. In support of the Volt and the efforts the good folks at Chevrolet are putting into it, I hope it gets better than the 40 mpg I got from my Cobalt.


RE: Not bad
By Hiawa23 on 10/16/2009 4:24:58 PM , Rating: 2
I have a 2009 Cobalt (2-door, 2.2 ltr./4cyl/manual transmission)...Columbus Day weekend I got 517 miles on a single 13 gallon tank of gas. In support of the Volt and the efforts the good folks at Chevrolet are putting into it, I hope it gets better than the 40 mpg I got from my Cobalt.

Wow, I am jealous. I have 2006 Mitsu Lancer Ralliart 2.4l & the best it does is 250-260/tank. The manual says it's a 13gallon tank but that can't be cause the most it will allow me to put in it is 10gallons.


RE: Not bad
By lewisc on 10/16/2009 1:32:53 PM , Rating: 2
I doubt he was looking at the driver. From the sample of workers in the first photo, 93% white, 100% male. Must be one hell of an office Christmas party - mistletoe, you say?


RE: Not bad
By Noya on 10/16/2009 4:47:27 PM , Rating: 1
Come on, you know it's setup.


RE: Not bad
By bobny1 on 10/17/09, Rating: 0
RE: Not bad
By XtremeM3 on 10/20/2009 3:04:14 AM , Rating: 2
I hope that is an attempt at humor, since you've also got a 20 gallon gas tank on your "oddy" - so basically saying that the 12.5 - 15mpg you are getting is comparable. I truly hope that was an attempt at humor, because a bad joke would give me more hope for Daily Tech reader intelligence than the blatant ignorance displayed with the attempt of a true comparison of the two.


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