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2011 Chevy Volt
But Volt's true nature may actually be an improvement, plus early reviews are complementary

In the week when auto editors turned in their first reviews of test drives of General Motors' upcoming 2011 Chevy Volt, there's been a bizarre twist that's largely overshadowed these initial impressions.

In a wild twist, Larry Nitz, GM's executive director of electric and hybrid powertrain engineering, has revealed that the gasoline engine actually will drive the Volt mechanically.

Previously, GM had maintained that the Volt was a battery electric vehicle (BEV).  When the battery's 40-mile range (since revised to "25 to 50 miles") was nearing exhaustion, a turbocharged 1.0-liter 3-cylinder gasoline engine kicked in, supply electrical current directly to the batteries and motor to provide more than 200 extra miles in range.

That platform was known as "E-Flex".  But unbeknownst to anyone, GM was pulling a bait and switch.

Today, Mr. Nitz revealed that 
actual powertrain.  The Volt, it turns out, is not a BEV like the 2011 Nissan Leaf.  It is actually a plug-in hybrid electric vehicle (PHEV) like the 2012 Ford Focus or 2012 Toyota Prius EV.

The internal combustion engine (ICE) -- now a 1.4L 84 hp 4-cylinder design -- and the 149 hp permanent-magnet AC electric motor both feed into a planetary gear set and three electronically controlled, hydraulically activated multi-plate clutches.  The resulting automatic transmission is marvel of electro-mechanical engineering offering a blend of efficiency and power.  The entire powertrain is bolted together to minimize noise, vibration, and harshness (NVH) and reduce space usage.

Arguably this advanced transmission is much better for customers than what GM initially 
said it was offering.  As Ford Motor Company pointed out in our recent interview with their head of electrification, BEVs suffer from poor performance in cold or hot weather, as the battery's performance deteriorates sharply. 

So why the bizarre farce on GM's part in claiming its BEV was really a PHEV, when the actual design would be more beneficial to the majority of customers?  Mr. Nitz claims that GM had to deceive the public in order to secure its patents on its unique transmission.  Now with the patents in hand, he was free to go public with the new powertrain platform, dubbed "Voltec", he says.

Turning to what GM had intended to be the focus this week, 
MotorTrend and The Detroit News have taken their first drives in the upcoming PHEV and are quite enthusiastic.

The Detroit News writes:

After I drove more than 32 miles on electric power only — in a very un-eco-friendly manner — the Volt’s little engine began powering the car. This was the moment I had been waiting for: It’s one thing to power a car with batteries, but it’s revolutionary to have a gas engine supply the power to electric motors.
The succession of power is more seamless than a presidential election. The engine is quiet and keeps humming along. There’s never a glitch, a pause or a moment when the engine noticeably kicks on or off. For the most part, once the initial battery charge is drained, the engine produces the electric power to drive the motor. 
...

Most of all, there's nothing to adjust to in the Volt. My 75-mile trip used a total of 0.9 gallons of gasoline. But I would have been happy to drive farther. 

And MotorTrend opines:

The Volt is no sports car, but it blows Toyota's plug-in Prius away (9.8 seconds to 60 mph), and runs neck and neck with a 2.4-liter Malibu in acceleration and handling tests. Figure-eight performance is virtually identical at 28.4 seconds and 0.59 g, and the Volt's 119-foot stops from 60 mph are just 3 feet longer-impressive, given its 226-pound weight disadvantage and low-rolling-resistance tires. (The Prius weighs 376 pounds less than the Volt, yet it just matches its 0.78g lateral grip, trails both Chevys by 0.4 second on the figure eight, and needs 131 feet to stop from 60 mph.)

Based on these reports it appears that GM's "surprise" of the ICE hooking up directly to the transmission to drive the wheels seems indeed to be a good one.  On the other hand, many will likely dwell on the fact that GM pulled a bait-and-switch on the customer.  

After all, some customers really want an honest-to-goodness BEV and may now being a bit bummed that they instead ordered what essentially amounts to a souped up plug-in hybrid.  Others have been vocal critics of the vehicle (and GM in general) and will likely jump on GM's deception as a platform to attack the vehicle (and GM in general).

Perhaps GM was right -- they had to mislead the public to protect their intellectual property.  But the move was certainly a very bad decision in terms of public relations.  GM can only hope that the public settles down and comes to realize the bottom line -- that it's offering them a superior package than what it initially promised to deliver.



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Bait and switch?
By ianweck on 10/12/2010 11:18:51 AM , Rating: 2
Wow Jason. I've read from other posters on other threads about how you can be either purposefully deceptive or just outright not know what you are talking about, but I had never really believed it until now.
Here is how it actually works:

quote:
"The drivetrain has a bit in common with the Prius and Ford hybrids. It consist of a single planetary gearset, two electric motors, and one gas engine. Motor Trend thinks the design is superior and more efficient than Toyota’s, and according to GM engineers with whom I spoke, is on the verge of patented.

There is a large central sun gear turned by the 149 horsepower electric motor at all times. Around it is a planetary carrier which turns the wheels. When the car is in charge depleting mode, an outer ring is locked to the case. The engine and generator are disengaged.

When the car reaches 70 mph the main motor spins too fast to be maximally efficient, and a clutch disengages the ring from the case. This allows the second electric motor to participate and both motors act in parallel to reach speeds of 101 mph with adequate power.

In charge sustaining mode, the gas engine goes on and clutches to the generator causing it to produce electricity to continue powering the main motor.

However of particular interest, when going above 70 mph in charge sustaining mode, and the generator gets coupled to the drivetrain, the gas engine participates in the motive force. GM says the engine never drives the wheels all by itself, but will participate in this particular situation in the name of efficiency, which is improved by 10 to 15 percent."


If you read carefully, it actually says that the electric motor will always power the wheels except in one condition: charge sustaining mode above 70 mph. Even then the gas engine is only assisting and isn't the sole source.
So in my opinion that's hardly a bait and switch.




RE: Bait and switch?
By mindless1 on 10/19/2010 4:02:14 PM , Rating: 2
In my opinion it's clearly bait and switch. IF it had cost closer to a plan ole ICE car I would have considered buying one, but THIS?

This is a frankenstein mobile, if you have the ICE engine and put a transmission on it to propel the car, then adding the weight, expense, and complexity/repair cost/frequency of the electric motor addition and battery pack is stupidity.

They basically removed even the virtues that even bubbleheaded green-fiends liked, now it is just a nonsensical feel good product with no point.


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