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Thanks for sharing...

Oy, GM marketing...

"This new eAssist system, when coupled with the four-cylinder engine, has a 19 percent increase in city fuel economy compared to the LaCrosse’s advanced V-6"

Thank GM for making than telling me a four banger more efficient than a V6...
 

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I can see why this could be a big deal if the La Crosse was a bigger seller. The hybrid becomes the standard engine configuration and is priced lower than the existing standard. So 19% better MPG and a lower price and likely faster and smoother acceleration. What's not to like?

Also makes one wonder why Mary Berra has taken the lead trying to change the CAFE standards.
 

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The number of cylinders has little direct tie in to efficiency or power.

2017 GM I4 2.0L economy engine = 275HP / 295ftlb - 22/25/31 mpg 3410lb
2017 Toyota V6 3.5L economy engine = 268HP / 246ftb - 21/24/30 mpg 3480lb

I would say virtually identical.
 

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...

Also makes one wonder why Mary Berra has taken the lead trying to change the CAFE standards.
It's a very old problem. Some folk believe car companies should only make cars people do not want to buy. Car company folk and the public want cars that serve the actual market.

So it's a compromise. Most car companies are making both. The new tighter CAFE goals were to be evaluated as time goes on. The fleets are still improving their economies, even the 'guzzlers' are achieving higher MPGs as time goes on. The question is how fast should we transition without destroying the US economy. Yes, a massive depression would reduce emissions, but might also reduce government programs.
 

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The number of cylinders has little direct tie in to efficiency or power.

2017 GM I4 2.0L economy engine = 275HP / 295ftlb - 22/25/31 mpg 3410lb
2017 Toyota V6 3.5L economy engine = 268HP / 246ftb - 21/24/30 mpg 3480lb

I would say virtually identical.
The I4 engine you picked is high performance turbo in the base camaro, manual states 91 is recommended and by using 87 your fuel economy will suffer...Not what I'd call "economy" yet on the Lacrosse it appears a sub 200hp engine is not available...
 

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The logic of going back to a BAS light hybrid approach in the LaCrosse escapes me. GM currently has a great full hybrid in the Malibu Hybrid, and this is a car using the same platform. The Malibu Hybrid uses a 1.8 liter ICE coupled to a slightly modified Voltec transmission. It has a 1.5 KWH battery and, I assume, the same inverter as the Volt to operate the Voltec transmission. This powertrain is capable of driving all electric up to 50 MPH and assists the ICE to feel much more powerful when it is operating. It is rated 48 city, 45 highway, 47 combined.

The new LaCrosse will have a 2.5 liter ICE coupled to a nine speed transmission. GM says it will get 25 city, 35 highway, 29 combined. The Belt/Alternator/Starter uses a puny 15 HP motor, so no chance of driving electric only and no chance of the smooth, torquey, drive characteristics of a Volt or even the Malibu Hybrid.

The key difference is the transmissions being used. I can't see that a nine speed transmission would be significantly cheaper than a Voltec transmission, not can I believe it can provide a more premium power delivery. Both vehicles have similar sized batterys and both use 3-phase AC synchronous motors (the Voltec uses two much more powerful motors) which requires an inverter to control motor operations.

What puzzles me is why offer a new, but less capable BAS powertrain on a higher end model when the Malibu Hybrid with better driving characteristics and efficiency is already available on the same platform? The Malibu Hybrid could also be expanded to a plug-in hybrid in the future by using the battery pack and charging units from the Volt. The BAS growth is pretty much limited to the belt's ability to handle power from the electric motor. I don't see it growing much more than the 15 HP it is now without resorting to a gear or chain drive which would add more complexity and cost.
 

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When I wrote the article a week or so ago, I thought this seemed like a good time to introduce a PHEV LaCrosse, so that it offered something more than the Malibu or the Chinese LaCrosse. I guess it was just wishful thinking.

But besides the 2.5L engine, the 2018 base model gets a 6-speed transmission. The new 9-speed is only paired with the 6-cyl engine.

In the ordering info for the LaCrosse, the BAS states it has a MG unit rated at 20 kW "continuous". I thought this could have insinuated a plug-in. It seems that the battery pack is the same as used in the limited pickup truck hybrids, a 24-cell pack with the same cells as used in the Malibu Hybrid.

It seems that one reason for this is the small battery can be packaged and still leave good trunk space (the newest eAssist system is discreetly packaged to maintain the LaCrosse’s fold-down rear seat and ample trunk space).

http://media.gm.com/media/us/en/buick/home.detail.html/content/Pages/news/us/en/2017/jun/0605-2018-lacrosse.html
 

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Well, they can still count this as one of the "electrified vehicles" GM is introducing this year. I myself have a higher bar for "electrified vehicle", however.
 

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One tidbit of info, this eAssist is the STANDARD engine while the V6 is optional...

Well, they can still count this as one of the "electrified vehicles" GM is introducing this year. I myself have a higher bar for "electrified vehicle", however.
This isn't the first time, looks like this was offered as early as 2012 and they claim it improved it by 25% improvement for the 2012 and that's over the four cylinder...

http://media.buick.com/media/us/en/buick/vehicles/regal-eassist/2012.html
 

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It's a very old problem. Some folk believe car companies should only make cars people do not want to buy. Car company folk and the public want cars that serve the actual market.

So it's a compromise. Most car companies are making both. The new tighter CAFE goals were to be evaluated as time goes on. The fleets are still improving their economies, even the 'guzzlers' are achieving higher MPGs as time goes on. The question is how fast should we transition without destroying the US economy. Yes, a massive depression would reduce emissions, but might also reduce government programs.
I can agree with all this but it doesn't affect my point. Actually two points. One is that GM is better positioned than most to meet CAFE. Two is that, even if it weren't, having its CEO be the point person on CAFE reduction is simply downright stupid from a PR standpoint. It's not going to succeed so it's tiling at windmills. At the same time it runs the risk of whacking off Millennials who view climate change as the most important issue facing the US. Since Millennials are the largest demographic cohort and the primary customer base for years to come, snubbing this group is something that should be avoided.

It seems that one reason for this is the small battery can be packaged and still leave good trunk space (the newest eAssist system is discreetly packaged to maintain the LaCrosse’s fold-down rear seat and ample trunk space).
I think this is right. GM went for space and cost. FWIW I thought your article was thought provoking and I enjoyed it.
 

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The number of cylinders has little direct tie in to efficiency or power.

2017 GM I4 2.0L economy engine = 275HP / 295ftlb - 22/25/31 mpg 3410lb
2017 Toyota V6 3.5L economy engine = 268HP / 246ftb - 21/24/30 mpg 3480lb

I would say virtually identical.
Not necessarily. Most of the time "there is no replacement for displacement" when it comes to performance. Of course the more cylinders, displacement in this case, you have the less fuel efficient your engine will be, in general.

2014 Volt Premium - Safety pkg 1 and 2, Navigation
 
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