GM 4-cylinder Models Hit 40% of Retail Sales in June, Doubling 2007 Figures

[Exploder]

Originally Posted by Ming

If you manufacture a fat, bloated, heavily cladded and un-aerodynamic mini-SUV crossover thingy that weighs far more than it should, jacked up on stilts to look more like a truck to show off its faux-by-four capabilities....(when a sedan-based wagon would hold the same 5 people and the same cargo more efficiently)...then the answer to your question is "not much".

Just curious...is that referring to a specific vehicle?

[RSW]

Originally Posted by eaton53

GM doesn't give away all their HP to gain a couple of mpg's. Examples:

The Corolla has 77% of the Cobalt 2.4's horsepower, but the Cobalt has 86% of the Corolla's fuel economy.
The Yaris has 60% of the Cobalt 2.4's horsepower, but the Cobalt has 80% of the Corolla's fuel economy.

Which ones are uncompetitive again??

And why Hondas are much better than Toyotas:
The Cobalt 2.4 has 86% of the Civic Si's horsepower, but the Civic has 92% of the Cobalt's fuel economy.
Pretty close, as long as if torque doesn't enter the equation.

And:
The Civic has 82% of the Cobalt 2.4's horsepower, but the Cobalt has 86% of the Civic's fuel economy.
Again, pretty close.

Well, the non-linear relationships you are citing (where more power than fuel economy is lost or gained) isn't surprising. After all, if one cuts a car's hp in half, it doesn't suddenly take half the fuel. Therefore we would expect that, for the Japanese cars to have say 10% better fuel economy, they might have to have 15 or 20% less power. That is one way they are once again beating America in fuel economy.

The root of this discussion as I understood it was about whether the Cobalt and its engine were competitive. If having a little more power and worse fuel economy is what people are after in this segment then I guess it is. But I think personally it would be a mistake for GM to assume, particularly looking toward the future, that fuel economy in this segment is a lower priority than any other factor.

[eaton53]

Originally Posted by RSW

The root of this discussion as I understood it was about whether the Cobalt and its engine were competitive. If having a little more power and worse fuel economy is what people are after in this segment then I guess it is. But I think personally it would be a mistake for GM to assume, particularly looking toward the future, that fuel economy in this segment is a lower priority than any other factor.

Actually it's about having A LOT more power and a little less fuel economy... the balance of power and performance of the Cobalt vs. the one-dimensional frugal turds that are the Toyotas.

I'm as cheap as the next guy but I'm not driving a turd to save a few pennies a day, which is what the difference amounts to.

It does look like GM may have caught on and will be offering the frugal turds in the not too distant future... the XFE's being the first step. That's fine and dandy as long as they still offer some hot ones, which Toyota does not do.

Therefore we would expect that, for the Japanese cars to have say 10% better fuel economy, they might have to have 15 or 20% less power. That is one way they are once again beating America in fuel economy.

Some do some don't... that's why I listed the Hondas and why they kick Toyota's butt.
Having driven both, there is simply no comparision between a Civic and a Corolla.

[44 mpg by 2010]

In this discussion about "larger" versus "smaller" engines it is not clear to me which is better ... horsepower or torque. I guess part of the underlying question is ... how flat are these parameters over the "normal" operating RPM range?

I need the forum help in trying to figure this "mess" out. Your thoughts, knowledge, comments, and criticisms would be appreciated.

If torque is the "parameter of preference", then it would appear ... to me ... that a small turbo diesel would win with its' significantly higher torque on the low end. And if diesel is used, there is the advantage of its' 15% higher energy content ... PLUS the higher overall engine efficiency ... allowing about at 30% better fuel economy ... OR HIGHER for a given engine size.

It is worth noting that not all diesels are created equal! I think this can be demonstrated with the following.

How many US production automotive diesel engines REDLINE above 3,000 RPM? I have asked this question on many automotive forums. So far none have been named. On the other hand, in Europe and much of the rest of the world, most of the "new generation" small automotive turbo diesels REDLINE above 4,000 RPM.

Also, many of these new Euro turbo diesel have overcome the "lag" that is generally noticed during acceleration.

So, if torque is what makes the machine go ... and torque lag has been generally resolved and flattened over a relatively large RPM range ... it seems to me that a noticeably smaller turbo diesel engine could be used in a given application with significantly lower fuel consumption (25 to 50%) while maintaining similar performance.

Of course diesel raises the emissions issue. However, at least 5 manufacturers seem to have found solutions. So the question that remains open is how much fuel economy must be sacrificed to achieve acceptable US emissions levels. If VW is an indicator ... there is not very much fuel economy loss to achieve California compliance .... from what I can see.

Some sources:
http://www.vcacarfueldata.org.uk/search/
http://www.vcacarfueldata.org.uk/sea...lConSearch.asp
http://www.autocar.co.uk/SpecsPrices...AndPrices.aspx
http://www.fueleconomy.gov/feg/2008b....jsp?year=2008
http://www.fueleconomy.gov/feg/2008b....jsp?year=2009

So folks, what is wrong with this logic???

[eaton53]

There are 4 problems with using a diesel.

1. Much higher engine cost.
2. Considerably more expensive fuel.
3. Dealing with greasy, smelly diesel fuel.
4. Diesel not as readily available as gasoline.

The first two are killers... because of #2 you can't save the money to make up for #1.

[ChevroletRevived]

I like the "GMI Flashbacks" Ming, that's always cool to do. This certainly is a GOOD PROBLEM to have though, just as it is with the Cobalt XFE situation. GM is increasing production and car sales are surging impressively. Only the people here can spin that as bad news.

[RSW]

Originally Posted by eaton53

It does look like GM may have caught on and will be offering the frugal turds in the not too distant future...

As usual, it is a matter of GM "catching on" late rather than leading. Just as GM catches where Honda and Toyota WERE, those guys will have moved on and leave GM trailing yet again. With fuel prices skyrocketing and a looming depression, the cheap/economical end of the market is incredibly important, and there it'll be mediocre Astras and Cobalts versus new products such as this Insight we are hearing about.