GM Volt 1.4 ICE Range Extender

[cfg83]

Hello -

dcb's series-hybrid thread led me to find this :

GM Explains Why the 1.4 L ICE Range Extender was Chosen For the Volt - July 26th, 2008

... why GM went with the 1.4 L non-turbo 4 cylinder engine and found out some other interesting things.
For one thing, per Nitz, "the 1.4L NA four has better brake-specific fuel consumption than the 1.0L turbo when used in steady state mode, as it will be in the Volt application."
Also Nitz claims the four cylinder engine will provide for a smoother transition from EV to range extension saying "the objective is to keep the engine off and when the engine comes on, you don’t want to know it’s on. You want it really smooth and four cylinder is smoother than a three."
Nitz also noted that the four cylinder has a lower cost and that when the turbocharging architecture is added to the 3-cylinder engine, the non-turbo four cylinder engine setup is actually lighter.

CarloSW2

[ldjessee00]

Ok, but why not use a diesel?

[bwilson4web]

Originally Posted by ldjessee00

Ok, but why not use a diesel?

Speculation, I suspect NO{x} emissions and weight. A simple, three-way, catalytic converter can handle gasoline emissions. Also, the lower stresses of the gas engine should give a higher power to weight ratio compared to an equivalent power diesel engine. For example, chain saws seldom use diesel cycles, with one exception, "Comet" from the 1950s.

Bob Wilson

[DonR]

Originally Posted by ldjessee00

Ok, but why not use a diesel?

Because they want it to work and they wanted to make it themselves.

Don

[dcb]

I do have issue with disguising the ICE operation. I think it should be a LOT more obvious that you are going to start burning fuel, or are burning fuel. Perhaps a personal preference, perhaps pandering to soft consumers, but If I bought something as presumptuously named as "volt" and discovered I had been running tons of fuel through it then I would be a little pissed, as someone who is trying to reduce petrol dependencies.

I have to wonder what the range extender is doing to cost/red tape/epa concerns/delays to market. And I have to wonder if GM wants to delay its release.

[Allch Chcar]

No kidding, a turbo on a range extender was a really dumb idea. They should have just use the 1.0liter then it would have been cheaper, lighter, and more efficient. But they decided to use the Volt as a Range Extender instead of a battery charger so once the battery hits it's Depth of Discharge boom it's ICE powered till you plug in the battery. Thankfully the inefficiency of going through the generator and the drive motor is at least respectable or it'd get worse efficiency than an ICE powered Volt.

There is other variables too. The durability of a 1.0liter Turbo could be less than the 1.4liter if it was ran with the turbo running even half of the time. Turboes are not a good choice on Electric Vehicles anyway.

Why use a diesel?
It's heavier and more expensive. That alone disqualified it before we had a chance to even consider. I'd love to discuss it more. Now with DI getting more expensive I don't doubt the price is becoming comparable to Diesels. But Diesel is necessary for Commercial vehicles so any more competition with business is bad in my book.

And I agree with you dcb. But when they build a mass market car that annoying ICE needs to be silent for them consumers. I don't mind a noisy car even if it is a bit annoying but the silent ones are the dangerous ones. The Prius received flak for being quiet at <35mph but many cars could run you over before you heard them coming at much faster speeds. Double standards. I grew up being extremely cautious about roads and when I did start spending a lot of time around traffic I would still be caught off guard by vehicles that I couldn't see or hear until they were too close for comfort.

[bwilson4web]

This is a side issue:

Originally Posted by Allch Chcar

. . . I don't mind a noisy car even if it is a bit annoying but the silent ones are the dangerous ones. The Prius received flak for being quiet at <35mph but many cars could run you over before you heard them coming at much faster speeds. Double standards. . . .

It turns out noisy SUVs and pickup trucks are the primary pedestrian killers. As for the Prius, the actual fatality rate is much less than the USA fleet:

Prius Fatalities 2001-2007

I would point out GM has not put noise makers on their existing hybrids ...

Bob Wilson

[dcb]

I knew that discussion would ring a bell with you Bob

[Old Tele man]

Originally Posted by bwilson4web

This is a side issue:
It turns out noisy SUVs and pickup trucks are the primary pedestrian killers. As for the Prius, the actual fatality rate is much less than the USA fleet:

Prius Fatalities 2001-2007

I would point out GM has not put noise makers on their existing hybrids ...

Bob Wilson

...does that mean EV's are like the prodigal kids, who should be "...seen, but not heard"?

[bwilson4web]

Tuesday morning, C-SPAN, Washington Journal, enjoy:

* Jim Campbell, General Motors Company, Chevrolet General Manager
* Susan Cischke, Ford Motor Company, Group Vice President
* Jim O'Donnell, BMW of North America, Chairman & CEO

Bob Wilson