Archives

"We don't know how to get 30 percent better mileage from RWD cars." (http://www.chicagotribune.com/classified/automotive/columnists/chi-0704090401apr10,0,7049242.column?coll=chi-business-hed)

http://www.cleanmpg.com/photos/data/501/Chevrolet_Camaro.jpgJim Mateja - Chicago Tribune - April 10, 2007

Chevrolet Camro concept scheduled for 2008 release may be one of GM’s last exclusively RWD automobiles.

General Motors has put a hold on future rear-wheel-drive vehicles.

"We've pushed the pause button. It's no longer full speed ahead," Vice Chairman Bob Lutz revealed in an interview.

Two of the most important RWD cars in the works are the Chevy Camaro sports coupe due back late in 2008 and the full-size, RWD replacement for the Chevy Impala sedan for 2009. Both are expected to be huge sellers and contribute major profits to a GM till burdened with IOUs the last few years.

"It's too late to stop Camaro, but anything after that is questionable or on the bubble," said Lutz, noting that also means Camaro derivatives -- along with a big Impala sedan, "if we call it Impala."

The RWD cars, you see, would be larger and heavier than front-wheel-drive cars or are high-performance models.

So it comes down to the matter of fuel economy. Or as Lutz says: "We don't know how to get 30 percent better mileage from" RWD cars.

That 30 percent bogey arises from a proposal by the Bush administration to raise corporate average fuel economy (CAFE) standards by 4 percent a year so cars would have to average 34 m.p.g. by 2017, up from 27.5 m.p.g. today. On top of that, the Supreme Court ruled last week that the Environmental Protection Agency can regulate carbon dioxide expelled by cars, a gas that contributes to global warming. The EPA doesn't do so now.

"We'll decide on our rear-drive cars when the government decides on CO(-2) levels and CAFE regulations," Lutz said, adding that limiting CO(-2) would increase mileage, too.

"Carbon dioxide is a natural byproduct of burning gas and directly proportional to the amount of fuel burned. If we legislate CO(-2) from cars, why not legislate we take one less breath per minute since humans release capricious amounts of CO(-2) each time they exhale?" offered a testy Lutz.

Lutz also points out that higher mileage will come at a price, with the proposal to raise CAFE certain to increase costs by as much as $5,000, which will be added to a car's sticker, an amount most consumers won't be willing to pay. There are no hard numbers for how much CAFE compliance adds to the sticker now.

"Rather than buy new, people would hang onto their old cars. We could eat the $5,000, but that would put us out of business."

Besides, those who see cars as more than just an appliance are eager for the new RWD offerings.

Among other cars affected are a high-performance midsize Pontiac, a replacement for the full-size Buick Lucerne sedan, a compact smaller than the current CTS at Cadillac and possible 300-horsepower versions of the Pontiac Solstice and Saturn Sky roadsters.

"This is very disappointing," noted Erich Merkle, director of forecasting for IRN Inc., in Grand Rapids, Mich. Most of the cars coming are necessary to GM's turnaround as showroom magnets.

"What the public buys makes CAFE work, not what the industry builds," Merkle added. "To improve mileage you change demand, not supply, by raising gas prices through taxes. But no politician is going to do that so they throw the responsibility on the back of the industry."

Lutz also objects to the talk that carmakers can easily raise mileage with a very low investment.

"Academics assure us that for $200 we can get 30 percent better mileage. If anyone can figure out how to do that for $200 -- or even for $1,000 -- I want them in my office today. Show me how to do it and we'll adopt it," he said. "If I could increase mileage by 30 percent for $200, why wouldn't I? What's my motivation not to when a gas-electric hybrid gets 27 percent better mileage and I hope someday to get the cost down to $9,000?"

Others insist that carmakers simply have to sell more small cars, such as the trio of 1-liter concepts that promise 40 m.p.g.-plus that GM unveiled at the New York Auto Show.

"Small-car mileage only counts toward CAFE if you build them here, and you can't build small cars here at a profit," Lutz said, explaining that foreign-made cars would count toward the automaker's import fleet, and its domestic fleet is where GM needs help.

"We don't know how to get 30 percent better mileage from RWD cars."[/url]Lutz also points out that higher mileage will come at a price, with the proposal to raise CAFE certain to increase costs by as much as $5,000, which will be added to a car's sticker, an amount most consumers won't be willing to pay.

People are simply too lazy to do the math, or don't have a good grasp of simple economic concepts, or both.

When we got out Jetta TDI, we got into a bidding war with people who were willing to get on a plane and fly to California to buy it cash. We ended up paying $2000 over bluebook for it, but were more than happy to do so, since we understood that we would make back that money in the increased FE savings.

Lutz wants to know how to increase FE by 30%? Include a hypermilling pamphlet with each new car they sell. It'd cost them less than $1 per vehicle and comply with CAFE! :Banane01:

It sounds to me like they're trying to make this a polotical issue, making it sound like fuel economy regulations mean that they're going to have to stop making performance cars entirely. If I understand them right, they're hoping that we will all get bent out of shape over it. Fine, I guess. Its true that RWD drivetrain losses are going to be a bit larger since you have an extra step or two to get power from engine to wheels. But enough to make or break a 30% improvement? Sounds like management-level engineering to me, which is usually a reason to smack one's forehead. It's also interesting to read what he's saying now against the fact that they have developed the 2-mode drivetrain specifically so that it can work with a big RWD platform like a truck. Would they spend that money on that technology if RWD is such a horrible thing from an FE perspective? Doubt it.

The US auto industry wouldn't be such a disaster if the executives just shut up and tried to **do** something rather than whine and market all day long. It makes me crazy.

i'm still debating if bob lutz is a hero or a whiner, this isn't the first time he whined about fuel economy.

Well, you can increase the FE of city driving pretty easily. All you gotta do is make the engine shut off when you're just sitting there. That eats up several % FE easily. They don't need anything like a hybrid has, just something that stores the energy from braking, like the hydraulics that were posted a while back, and a slightly larger starter motor to start the engine with. If you could have the starter motor power the gas engine to even 750 RPMs or so it would hurt the engine a lot less and then you could basically start and stop the engine at will.

The hydraulics were supposed to be relatively cheap and getting a slightly bigger starter motor should be that expensive.

Not sure exactly how much more FE you'd get out of it, but it sure the hell would be noticeable.

Take a look at the BAS system in the Saturn VUE. A simple shut of engine at lights doesn't give that much FE savings. It gives a little, but nowhere near 30%.

I believe an instant fuel economy display would probably save just as much as people see 20mpg in a vehicle rated for 30. They will start to wonder why and will start to change habits when they see what their driving is doing to their mileage.

The RWD cars, you see, would be larger and heavier than front-wheel-drive cars or are high-performance models.

last time i checked it was possible to make a small car that was RWD.... come on now bob, this is absurd, your company makes the solstice and the sky :flag:

Its true that RWD drivetrain losses are going to be a bit larger since you have an extra step or two to get power from engine to wheels.
I've allways been under the impression that FWD is less efficient, can anyone confirm that FWD is more efficient? (mind you i dont really know much about FWD transmissions)

$5,000? Give me a break! Hybrid technology adds about $3,000 to the price of a car and it adds about 40-50% to the fuel economy. People seem to snap then right up. The GM dilemma is this only care about making bloated SUVs.

last time i checked it was possible to make a small car that was RWD.... come on now bob, this is absurd, your company makes the solstice and the sky :flag:


I've allways been under the impression that FWD is less efficient, can anyone confirm that FWD is more efficient? (mind you i dont really know much about FWD transmissions)

The advantage of FWD is space and weight savings, but the downside is it's more expensive to repair than RWD. Also, it's more likely to get broken in a collision if it's FWD.

Does anyone know if there are FWD pickups?

I'm not real car savy, but couldn't you move the engines to the back like the old VW bugs? It's the same as having the engine in the front for FWD right?

I'm not real car savy, but couldn't you move the engines to the back like the old VW bugs? It's the same as having the engine in the front for FWD right?

Wish it was safe.

Does Ralph Nader and his book on the Corvair Unsafe at Any Speed? ring a bell?

The Corvair was a mid-sized version of the VW beetle. Nader stated 50-60 Corvair deaths were the result of drivers taking a sharp turn at highway speed, then like a sling, it flies off rear-end first. :( I remember driving the one in the family - steering was as effortless as a bike because 60% of the weight was in the rear.

Also, a Czech car company had rear-engine cars. After the Germans occupied their country, they eventually ordered their officers not to drive them because it was a death trap.

... I've allways been under the impression that FWD is less efficient, can anyone confirm that FWD is more efficient? ...

I heard that it's a lot less expensive to build a FWD because they assemble engine and tranny and drop it in - done. No driveshaft and diff + axle to deal with located down at the other end of the car. True those components have to be there - but they're all in one unit and get dropped in together.

I thought FWD has bettter FE due to more efficient use of space. Less wasted space in the vehicle, that is space that doesn't give you more passenger or cargo volume. However now after decades of FWD R&D, I'd think that many of the layout concepts could be transferred to RWD cars. Except the driveshaft tunnel. A RWD will still need that tunnel unless you lift the body by the same amount - which would have its own weight and FE penalties.

Not that I'm trying to promote FWD or RWD over the other option. My car is RWD and I really like the handling, but I do believe that FWD has better traction, all other things being equal.

FWIW, some sports cars are mid-engine. Supposedly ideal handling, but really not possible for a car w/two or more rows of seats. The 2-seater mid-engine cars basically have the engine pretty close behind the driver. Very good front-rear balance for good handling. Pontiac Fiero is one.

Interestingly, hybird battery packs are in the rear of the vehicle to help out the front/rear balance.

FWD is more efficent because usually the drive wheels is right next to the engine, sending power from the FRONT to the REAR in a RWD config (using a driveshaft) is usually negated as a power loss (30% is usually this magic number). For efficency FWD usually weigh less as well contains less parts than a RWD car, as well being cheaper to fix and maintain. Which is why Honda is the king when it comes to FWD cars as well picking up for being the greenest automaker.

But for racing, FWD is garbage imo (tires in the front wear out too quickly as well as more power is introduced, handling and torque steer becomes a serious issue) . I'll take a RWD or mid engine config anyday.