Cruze Eco MPG shows that displacement doesn't matter much

[dwightlooi]

GM just announced the official MPG numbers for the Cruze Eco model:

http://media.gm.com/content/media/us/en/news/news_detail.brand_gm.html/content/Pages/news/us/en/2010/Nov/1111_cruze_eco

This pretty much confirms something I have been saying for years -- reducing displacement has a very small and sometimes intangible effect on fuel economy. Other factors such as weight, aerodynamics, transmission efficiency and friction within the engine has a greater bearing on mpg numbers.

If you look at the automatic numbers and compare it to that of the Ford Focus which has a 2.0L engine, you'll notice that it is but 1~2 mpg off. Given that the non-Eco 1.4T Cruze (Automatic) is turning in 24/36 mpg, we can also conclude that practically all of that is from aerodynamics improvements and weight reductions.

In other words, going from 2.0 liters to 1.4 liters gained you exactly nothing. This shouldn't be surprising given that displacement reductions itself without reduction in cylinder count, cams or valves does not reduce the internal friction of an engine by much. Yes, a smaller displacement engine pumps less air per revolution but at low loads and cruising speeds the amount of air moved is pretty much constricted by the throttle body anyway. We see the same lack of economy gains when we compare the 3.0 DI V6 and the 3.6 DI V6 too. The 3.0 is no more efficient than the 3.6 in the same vehicle, it is in fact less 1 mpg efficient due to reduced torque ratings forcing larger aggregate throttle openings.

I think this should give everyone pause when touting the reduction in engine displacement as a (leading) measure to improve fuel economy. You are better off reducing the cylinder count (without dropping displacement), reducing the number of camshafts, improving the transmission, working on the aerodynamics and/or cutting weight.

[Drew Dowdell]

and especially cutting weight

[Cory Wolfe]

Weight loss always wins.

This is, perhaps, the only Cruze to really consider.

[dwightlooi]

and especially cutting weight

Which begs the question... why isn't most of what's being done to the Eco model standard on all Cruzes? Especially stuff that is cost neutral or has a minimal effect on cost...

Eg. Less openings in the upper grill? That doesn't cost anything. Thinner gauge steel and narrower flanges? Costs zero, may even save a few bucks. An extended front air dam strip? Cost zero. Underbody tray? Costs a few bucks, but a piece of unpainted plastic or two really doesn't cost that much. Spoiler? OK make that an option. Light weight alloy wheels? OK, I'll drop that but everything else looks like they should be standardized.

They really ought to give the Eco Model something significant -- like a clutched automatic (ala M-B AMG), a dual clutch gearbox (don't develop one if they can't afford to, go buy Bord-Warner's off the shelf box like VW-Audi did) or a DI version of the 1.4T with higher compression. Dumbing down the standard ones to make the Eco stand out is... well... rather foolish.

Eco or not, the overwhelming majority of Americans don't buy Manuals -- they don't even know how to drive one. And, those who do? They are performance junkies not eco freaks.

Edited November 11, 2010 by dwightlooi

[Z-06]

Which begs the question... why isn't most of what's being done to the Eco model standard on all Cruzes? Especially stuff that is cost neutral or has a minimal effect on cost...

Eg. Less openings in the upper grill? That doesn't cost anything. Thinner gauge steel and narrower flanges? Costs zero, may even save a few bucks. An extended front air dam strip? Cost zero. Underbody tray? Costs a few bucks, but a piece of unpainted plastic or two really doesn't cost that much. Spoiler? OK make that an option. Light weight alloy wheels? OK, I'll drop that but everything else looks like they should be standardized.

They really ought to give the Eco Model something significant -- like a clutched automatic (ala M-B AMG) or a DI version of the 1.4T with higher compression. Dumbing down the standard ones to make the Eco stand out is... well... rather foolish.

Probably some part of GM is still same old. I agree with you 100% there. Why add a caveat with "Eco" for mpg numbers when you can make these changes across the Cruze models.

[regfootball]

there should be a CVT Eco to go with the stick.. in my experience the CVT can be programmed to run much lower rpm than a stick or stepped auto at highway speeds. Base cruze engine should be a 1.8 turbo.

[deftonesfan867]

Which begs the question... why isn't most of what's being done to the Eco model standard on all Cruzes? Especially stuff that is cost neutral or has a minimal effect on cost...

Eg. Less openings in the upper grill? That doesn't cost anything. Thinner gauge steel and narrower flanges? Costs zero, may even save a few bucks. An extended front air dam strip? Cost zero. Underbody tray? Costs a few bucks, but a piece of unpainted plastic or two really doesn't cost that much. Spoiler? OK make that an option. Light weight alloy wheels? OK, I'll drop that but everything else looks like they should be standardized.

They really ought to give the Eco Model something significant -- like a clutched automatic (ala M-B AMG), a dual clutch gearbox (don't develop one if they can't afford to, go buy Bord-Warner's off the shelf box like VW-Audi did) or a DI version of the 1.4T with higher compression. Dumbing down the standard ones to make the Eco stand out is... well... rather foolish.

Eco or not, the overwhelming majority of Americans don't buy Manuals -- they don't even know how to drive one. And, those who do? They are performance junkies not eco freaks.

Because then all Cruzes wouldn't have the Z watts suspension or any of the other goodies.

[regfootball]

generally i think the mpg of the eco won't be that much more in the real world. one component here is the low rolling resistance tires. generally those suck in cold weather / snow. the eco loses some sound deadener. also the non eco has the better suspension and the last two gears are different i think.

real world combo driving what does the regular cruze manual get vs the eco? 2 mpg difference is my guess. i think a non eco cruze manual should peg close to 40 for most folks on semi flat open interstate. i doubt the eco handles very well in comparison.

[dwightlooi]

Honestly, I would have powered the "regular" Cruzes with a normally aspirated version of the 2.0 DI Turbo engine. Should be good for 170~180hp and be a better engine for most drivers. You'll probably end up with similar MPG numbers as he Focus -- 24~25 mpg (city) / 34~36 mpg (Fwy). I don't think most buyers will care that much about + - 1 mpg when considering their purchases. A test drive in a car with a smooth, free breathing 170~180hp 2 liter engine will probably sway more buyers than 1 mpg.

They can the do an Eco Model using a 3-cylinder 1.8 liter milled that's basically the 3.6 V6 chopped in half. With a turbo the engine is probably good for the same 170~180 hp as the 2.0 four potter and at least equal the 1.4T four in economy numbers because it has 1/4 fewer frictional elements. This is especially true if it retains the 11.3:1 compression of the 3.6 and use minimal boost (7~8 psi). It'll also be relatively easy on logistics, sharing the rods, pistons, valves, valve cover and heads with the V6. A single balancing shaft should tame it sufficiently to be unobtrusive. The Eco can go full tilt with a dual clutch tranny, aluminum body work and what not.

That should be good enough for the launch. In the second or third model year, they can follow up with a 260~300hp 2.0T for the enthusiasts and keep the interest level in the model high.

The 2.0T and the Eco should be priced similarly. Basically, if the base car is not good enough the choice is between Performance and Green, drawing on both demographic niches.

Edited November 12, 2010 by dwightlooi

[NINETY EIGHT REGENCY]

Chevy's 2011 Cruze Eco: 42 mpg highway, 28 mpg city

Christina Rogers / The Detroit News

Chevrolet's new 2011 Cruze Eco will get 42 mpg highway and 28 mpg city, according to new estimates released today by the Environmental Protection Agency.

The mileage figures, based on models with a six-speed, manual transmission, put the Cruze Eco at the forefront of fuel economy in its class, beating out some larger hybrid vehicles and smaller cars sold by its competitors, such as Ford Motor Co.'s Fiesta, which gets 40 mpg highway.

The Cruze Eco — GM's more fuel-efficient version of its all-new compact — goes on sale in January with a price tag of $18,895, about $1,900 more than the base model.

With an automatic transmission, the Eco gets an EPA-estimated 26 mpg city and 37 mpg highway.

The Eco has a smaller 1.4-liter turbo engine than the standard Cruze LS, which is equipped with a 1.8-liter engine and gets 26 mpg city and 36 mpg highway with a manual transmission.

The Cruze began arriving in dealers' showrooms in late September and is General Motors Co.'s latest shot at putting a small, entry-level car on the market that will rack up large sales volumes for the automaker.

With the Cruze Eco, GM says it buyers can achieve better gas mileage than some of the segment's top-selling leaders, such as Toyota's Corolla, which gets 35 mpg highway, and Honda's Civic, which gets 34 mpg highway.

The Cruze Eco even beats out some hybrids in fuel economy but with a much lower sticker price. The Toyota Camry Hybrid, for instance, gets 33 mpg city and 34 mpg highway and costs $26,150, the automaker said.

Ford Motor Co.'s Fusion Hybrid, however, did beat the Cruze Eco — at least in city driving with an EPA-estimated fuel economy of 41 mpg. But the Cruze Eco trumped it on the highway with the Fusion hybrid averaging 36 mpg.

From The Detroit News: http://detnews.com/article/20101111/AUTO01/11110461/Chevy-s-2011-Cruze-Eco--42-mpg-highway--28-mpg-city#ixzz151Y79Aqy

[67impss]

Honestly, I would have powered the "regular" Cruzes with a normally aspirated version of the 2.0 DI Turbo engine. Should be good for 170~180hp and be a better engine for most drivers. You'll probably end up with similar MPG numbers as he Focus -- 24~25 mpg (city) / 34~36 mpg (Fwy). I don't think most buyers will care that much about + - 1 mpg when considering their purchases. A test drive in a car with a smooth, free breathing 170~180hp 2 liter engine will probably sway more buyers than 1 mpg.

They can the do an Eco Model using a 3-cylinder 1.8 liter milled that's basically the 3.6 V6 chopped in half. With a turbo the engine is probably good for the same 170~180 hp as the 2.0 four potter and at least equal the 1.4T four in economy numbers because it has 1/4 fewer frictional elements. This is especially true if it retains the 11.3:1 compression of the 3.6 and use minimal boost (7~8 psi). It'll also be relatively easy on logistics, sharing the rods, pistons, valves, valve cover and heads with the V6. A single balancing shaft should tame it sufficiently to be unobtrusive. The Eco can go full tilt with a dual clutch tranny, aluminum body work and what not.

That should be good enough for the launch. In the second or third model year, they can follow up with a 260~300hp 2.0T for the enthusiasts and keep the interest level in the model high.

The 2.0T and the Eco should be priced similarly. Basically, if the base car is not good enough the choice is between Performance and Green, drawing on both demographic niches.

Dwight what are your thoughts on a 3L slant I4 based on the Gen V pushrod V8 it could be made off the 8's tooling and used in FWD or RWD cars & trucks NA or turboed I like that idea as GM has said the Gen V was to be engineered CIB & OHC

[NINETY EIGHT REGENCY]

2011 Chevrolet Cruze Eco rated at 42 mpg highway

by Steven J. Ewing (RSS feed) on Nov 11th 2010 at 12:31PM

General Motors has released official fuel economy numbers for the 2011 Chevrolet Cruze Eco, and the automaker's original target of 40 miles per gallon (highway) has been surpassed. The Cruze Eco is officially rated at 28/42 mpg with the six-speed manual transmission, making it the segment-leader in terms of efficiency.

To achieve this, the Eco uses GM's latest 1.4-liter turbocharged inline-four, rated at 138 horsepower and 148 pound-feet of torque. On its own, the engine is efficient enough to deliver 24/36 mpg, but a host of aerodynamic changes and weight reductions on the Eco account for the extra bump in fuel economy. In addition to a lower front air dam extension, rear spoiler, lowered ride height and revised underbody panels, the Cruze Eco rides on lightweight 17-inch alloy wheels wrapped in low-rolling-resistance tires. What's more, a front grille shutter has been developed to improve airflow at higher speeds, thus accounting for a 10 percent coefficient of drag over standard Cruze models.

The Cruze Eco is priced from $18,895 and hits dealerships in January of next year. For the full details, hit the jump for GM's press blast.

New Chevrolet Cruze Eco Achieves Segment-Leading 42 MPG On The Highway

Hybrid-Like Fuel Economy Starts at $18,895; Goes on Sale in January

DETROIT – The official fuel economy numbers for the 2011 Chevrolet Cruze Eco are in and they're good. Segment-leading good. It delivers an EPA-estimated 42 mpg on the highway (manual transmission models), with equally impressive city fuel economy of 28 mpg.

Cruze Eco's highway fuel economy beats non-hybrid segment competitors – including 23 percent greater highway fuel economy than the Honda Civic – as well as the Ford Fiesta subcompact and many hybrid models. In fact, it's better than Ford Fusion Hybrid, Nissan Altima Hybrid and Toyota Camry Hybrid.

"Chevrolet Cruze continues to redefine the compact segment, offering class-leading standard safety features, upscale amenities – as well as hybrid-like fuel economy without the price," said Chuck Russell, vehicle line director. "The Cruze Eco is in a league of its own and will challenge perceptions of the efficiency available in a more affordable non-hybrid."

The Cruze Eco carries an MSRP of $18,895 (including destination charge). It goes on sale in January.

To achieve its segment-leading fuel economy, Cruze's engineers focused on aerodynamic performance, mass optimization and powertrain enhancements. The refinements in each area paid big dividends towards the car's overall efficiency, while providing engineers with valuable information to help enhance the efficiency of future Chevrolet models.

"We left no stone unturned or piece of sheet metal un-weighed," said Russell. "Our engineers were comprehensive and thorough when it came to evaluating and modifying the aspects of the car's performance that contribute to fuel economy."

Aero enhancements

Aerodynamic improvements over non-Eco manual-transmission models contributed approximately six mpg to the Cruze's EPA-estimated 42 mpg highway fuel economy. Many were developed and refined in more than 500 hours of wind-tunnel testing of the Chevy Volt, which shares a core architecture with the Cruze. Examples include the upper grille, which has more "closeouts" to improve aerodynamics, a lower front air dam extension, a rear spoiler, a lowered ride height and underbody panels that smooth airflow beneath the car.

The Eco model also features an all-new technology in the compact segment: a lower front grille air shutter that closes at higher speeds to reduce aerodynamic drag and opens at lower speeds to optimize engine-cooling airflow. Another contributor to reduced drag is the use of ultra-low rolling resistance 17-inch Goodyear tires (used with lightweight wheels), which are also used on the Volt.

As a result of the aero enhancements, aerodynamic drag was reduced by 10 percent over a non-Eco model, with a coefficient of drag of 0.298. That places Cruze at the top of the class for mainstream compact cars.

Mass optimization

More than 42 changes were made on the Eco to reduce weight. It weighs in at 3,009 pounds (1,365 kg), compared to the 3,223 pounds (1,462 kg) of the Cruze 1LT. The diet program for the Cruze challenged engineers to look at all aspects of the vehicle's construction, including hundreds of weld flanges on the vehicle. They were reduced 1 mm to 2 mm in length, which saved several pounds, while the sheet metal gauge thickness was reduced by about 0.1 mm in select components. This saved weight while preserving structural integrity.

Lighter wheels and tires are used on the Eco. They're stylish, polished 17-inch alloy units with Goodyear tires that weigh only 36.5 pounds (16.6 kg) apiece. That's 5.3 pounds (2.4 kg) less than the 16-inch wheel/tires of the Cruze 1LT for a complete savings to the vehicle of 21.2 pounds (9.6 kg).

Efficient powertrain

Cruze Eco is powered by power-dense Ecotec 1.4L turbocharged engine and a standard six-speed manual transmission. The transmission's gearing is optimized for the model's specific 17-inch wheel/tire combination and includes aggressive ratios for first and second gear coupled with a highly efficient, "taller" sixth-gear ratio for highway driving. That means engine rpm is reduced on the highway, which in turn reduces fuel consumption. A six-speed automatic transmission is available, with EPA-estimated fuel economy ratings of 26 city and 37 highway.

The Ecotec 1.4L turbo's power ratings are 138 horsepower (103 kW) and 148 lb.-ft. of torque (200 Nm) between 1,850 rpm and 4,900 rpm. The wide rpm range for the maximum torque – a specific trait of turbocharged engines – helps the engine deliver a better driving experience and performance. The turbocharger is integrated within the exhaust manifold, for reduced weight and greater packaging flexibility.

The engine also features premium design elements that give it world-class smoothness and durability while also contributing to the Cruze Eco's lower curb weight. They include a cast iron block with a hollow frame structure, hollow-cast camshafts and a plastic intake manifold.

Comparing the competitors

As a result of aerodynamic improvements, mass reduction and powertrain optimization, the Cruze Eco offers the best fuel economy in the compact segment, while delivering hybrid-like fuel economy without the hybrid price. The following charts show how it compares with primary competitors and popular hybrids.

link:

http://www.autoblog.com/2010/11/11/2011-chevrolet-cruze-eco-rated-at-42-mpg-highway/

[CanadianBacon94]

On its own, the engine is efficient enough to deliver 24/36 mpg, but a host of aerodynamic changes and weight reductions on the Eco account for the extra bump in fuel economy. In addition to a lower front air dam extension, rear spoiler, lowered ride height and revised underbody panels, the Cruze Eco rides on lightweight 17-inch alloy wheels wrapped in low-rolling-resistance tires. What's more, a front grille shutter has been developed to improve airflow at higher speeds, thus accounting for a 10 percent coefficient of drag over standard Cruze models.

This just backs up exactly what dwight said, that its not the engine that does the fuel economy improvements

[NINETY EIGHT REGENCY]

CHEVROLET ANNOUNCES 42 MPG HIGHWAY FIGURE FOR CRUZE ECO

By Andrew Ganz

Chevrolet has announced official EPA mileage figures for its green-minded Cruze Eco model. When equipped with a six-speed manual transmission, the Cruze Eco is capable of 4 2mpg on the highway and 28 mpg in the city.

The Cruze Eco features a number of changes aimed at decreasing fuel consumption, like an optimized front axle ratio and ultra low rolling resistance Goodyear tires and lightweight 17-inch alloy wheels. A lowered stance reduces mpg-robbing air turbulence at highway speeds, while a lower front grille “air shutter” closes at higher speeds to improve highway aerodynamics. Chevrolet also modified the upper grille and added in a new front lower air dam extension and a rear spoiler to make the Cruze Eco even more slippery to the wind.

The Cruze Eco will come standard with the aforementioned six-speed manual, but it will also offer a six-speed automatic. The automatic version of the Cruze Eco is slightly less efficient than its manual counterpart, earning an EPA rating of 37mpg highway/26mpg city.

Regardless of transmission, the Cruze Eco will come standard with the 138-horsepower, 148 lb-ft. of torque 1.4-liter turbocharged Ecotec four-cylinder rather than the base Cruze LS’ naturally aspirated four-cylinder. With that turbocharged engine, Chevrolet says that the Cruze Eco should be good for a 0-60 mph sprint of about 9 seconds with the manual and 10 seconds with the automatic.

Look for the Chevrolet Cruze Eco model to roll into dealer showrooms in January, carrying a sticker price of $18,895.

link:

http://www.leftlanenews.com/chevrolet-cruze-eco.html

[NINETY EIGHT REGENCY]

New Chevrolet Cruze Eco Returns 42 mpg Highway, 28 mpg City

THURSDAY, NOVEMBER 11, 2010

General Motors announced today that the Chevrolet Cruze Eco, which goes on sale in January 2011 for $18,895, delivers an EPA-estimated 42 mpg (5.6 lt/100 km) on the highway and 28 mpg (8.4 lt/100 km) in city, delivering a better fuel efficiency than hybrid models like the Ford Fusion Hybrid or Toyota Camry Hybrid.

The Detroit automaker's engineers achieved this by making the powertrain more efficient, further reducing the car's weight and improving the Cruze's aerodynamic coefficient.

The Cruze Eco is powered by a 1.4-liter turbocharged four-cylinder, delivering 138 hp and 148 lb-ft (200 Nm) of torque. To get the most out of it, GM optimized the torque range and made the peak value constant between 1,850-4,900 rpm. Furthermore, the transmission's gearing has been adjusted for the model's 17-inch wheel and tire combination. Low gears have aggressive ratios, while the sixth is a "tall" gear, better suited for highway driving.

The announced fuel economy concerns the model with the manual transmission , but there's also a 6-speed automatic available, with EPA-estimated fuel ratings of 26 mpg (9.05 lt/100 km) city and 37 mpg (6.53 lt/100 km) highway.

The Cruze Eco underwent a thorough mass-optimization process as well. It tips the scales at 3,009 lbs (1365 kg), meaning it's 214 lbs (97 kg) lighter than the Cruze 1LT. Weight-saving measures include the use of lighter wheels and tires, as well as reduced weld flange length and sheet metal gauge thickness.

Aerodynamic improvements are just as important when aiming for low fuel consumption and the Cruze Eco is a rolling proof of this. According to GM, "aerodynamic improvements over non-Eco manual-transmission models contributed approximately six mpg to the Cruze's EPA-estimated 42 mpg highway fuel economy." Engineers used lower front air dam extensions, rear spoiler and underbody panels that smooth the airflow beneath the car. They also lowered the ride height.

The technical tour de force is completed by the air shutter incorporated in the lower front grille that closes at higher speeds to reduce drag and opens at lower speeds to optimize engine cooling.

Below you can see how the Cruze Eco stacks up to non-hybrid and hybrid competitors

By Csaba Daradics

link:

http://carscoop.blogspot.com/2010/11/new-chevrolet-cruze-eco-returns-42-mpg.html

[smk4565]

42 mpg is impressive, but I suspect the great majority of Cruzes will be automatics. Still 26/37 mpg is right at the top of the class for now, new Focus and Elantra come in the spring so we'll have to wait to see what they get. The 2012 Focus has 160 hp though, I'd trade 1 mpg for an extra 20 horses.

[NINETY EIGHT REGENCY]

GM will have an interesting Chevrolet showroom. They will have Cruze on one side and Volt on the other. Cruze may pick up some Volt buyers who cannot afford the Volt.

[dwightlooi]

Dwight what are your thoughts on a 3L slant I4 based on the Gen V pushrod V8 it could be made off the 8's tooling and used in FWD or RWD cars & trucks NA or turboed I like that idea as GM has said the Gen V was to be engineered CIB & OHC

(1) If you are going to stick with the Pushrod-OHV layout, as you move to an inline configuration all of the advantages disappear. A pushrod valvetrain's advantage is in making a Vee type engine narrower, lighter and in some ways more efficient. It does so by reducing the number of camshafts, by making the heads narrower and lighter, and in doing the aforementioned cut down of parasitic frictional drag from the valve train. When you no longer have two banks of cylinders, all of that goes out the window.

(2) From an efficiency standpoint, if you compare two engines of the same displacement but different cylinder count, the one with fewer cylinders tends to be more efficient. Again, because of lower drag from fewer sets of piston, rod and valve assemblies. This however only applies up to a point... as cylinders get bigger, the distance from the spark plug to the edge of the combustion chamber also gets longer. This makes the engine less resistant to knocking. This forces you to lower compression ratio to compensate and that reduces fuel efficient by lowering the thermal efficiency of the combustion process. At some point you break even and start losing more efficiency to compression reduction than you gain in frictional reductions. A 3.0 liter four with 750cc cylinders is pretty close or beyond that point.

(3) A 4-potter also has 2nd order vibrations that get progressively worse with piston weight and especially stroke length. You can cancel most of it with a pair of contra-rotating balance shafts. Most of it, but not all of it. A 3.0 liter four with balancers will be a little on the rough side. Probably not horrendous, but definitely not a creamy smooth engine.

(4) A 3.0 liter 4-cylinder has actually been tried before on a production car. It was used by none other than Porsche on the 968. The engine made 236 hp in naturally aspirated trim and 305 hp in turbocharged trim.

[Drew Dowdell]

Wasn't that 4-cylinder Porsche a boxer engine though? Those have different vibration characteristics.

[67impss]

Wasn't that 4-cylinder Porsche a boxer engine though? Those have different vibration characteristics.

Nah "Front longitudinal inline four cylinder water cooled 16v VarioCam"

The 968 is a sports car sold by Porsche AG from 1992 to 1995. It took over the entry-level position in Porsche's lineup from the 944, with which it shared about 20% of its parts. The 968 became the final model in an evolving line, starting almost 20 years earlier with the introduction of the Porsche 924 and ending with the Turbo S, Turbo RS, and Turbo RS Lemans, which are three separate versions of the 968.

[67impss]

Dwight understanding the knock tendency of 4"+ bores, if the engine were to be a family ie V8 & 6 / I4 & 3this still could be quite a powerhouse for the investment. I read that GM's test mule made 450 bhp (340 kW) on gasoline via direct fuel injection, increased compression ratio to 11.5:1, and a modified engine controller.

[NINETY EIGHT REGENCY]

Chevrolet Cruze Eco could be GM's game changer

08:47 AM

The new Chevrolet Cruze Eco and its 42 mile-per-gallon highway gas mileage rating is likely to send the rest of the auto industry scrambling. Suddenly, every chief engineer is going to have to measure the fuel mileage of vehicles under development against a General Motors sedan.

It could be a painful exercise. At 42 mpg with a manual transmission, Cruze Eco is 2 mpg better than even GM had forecast. More significantly, it bests smaller cars like Honda Fit and Ford Fiesta. It's better than some hybrids, which can cost a lot more.

How did Chevy do it? It added more body panels to reduce wind drag, among other things.

Now other automakers are going to have to struggle for mpg boasting rights. A new Hyundai Elantra could deliver. So could the next Honda Civic. But if they can't best 42 mpg or come close, there could be hell to pay when sales are counted. Interestingly, even though gas prices have remained stable below $3 a gallon, surveys show buyers still care a lot about fuel conservation.

Cost is the key. Adding hybrid systems, turbochargers or diesel engines significantly increase their cost. The Cruze Eco will be more expensive than the base model, but won't blow the bank. Cruze Eco starts at $18,895, including shipping. The base model Cruze starts at $16,995. Chrissie Thompson of the Detroit Free Press says that's at least several hundred dollars more than its targeted foreign competitors, but Cruze Eco comes with more standard features.

The company will start building the Eco model this month, spokeswoman Lesley Hettinger tells the Free Press. Sales of the Eco model start by the end of the year, she said.

Just how does Cruze Eco's manual-transmission fuel economy stack up?:

At 28 m.p.g. city / 42 m.p.g. highway, it compares with the 26 / 35 offered by the Toyota Corolla, the Honda Civic's 26 / 34, the Ford Focus' 25 / 35 and the Hyundai Elantra's 26 / 35.

link:

http://content.usatoday.com/communities/driveon/post/2010/11/chevrolet-cruze-eco-could-be-gms-game-changer/1

[dwightlooi]

Dwight understanding the knock tendency of 4"+ bores, if the engine were to be a family ie V8 & 6 / I4 & 3this still could be quite a powerhouse for the investment. I read that GM's test mule made 450 bhp (340 kW) on gasoline via direct fuel injection, increased compression ratio to 11.5:1, and a modified engine controller.

Well, let's put it in a rough perspective. Going from a 89mm bore to a 94mm bore costs 0.4 points in compression (same cylinder head design, same fuel grade, same basic engine architecture). A 103.25 mm bore will likely cost you another 0.6 points or so.

What that means is that a 3.0 4-potter built on the Small Block architecture and using direct injection is likely to be a 10.7:1 (on regular fuel) to 11.2:1 (on premium fuel) engine. This is with the same level of conservatism as the HF V6 family. You can likely push it to 11.5:1 with a more aggressive attitude towards tuning like you might see in an engine destined for the Corvette or a Caddy Sports Sedan -- where Premium is not just recommended but required. You are unlikely to see that in a truck or family sedan engine which has to be more... let's say... idiot proof.

That said, a 3.0~3.1 liter 2v per cylinder DI 4-potter may not be a bad engine for entry level trucks. It'll make about 200hp on regular with a similar amount of torque. You can also fortify it with a single turbo to the tune of about 280 hp / 280 lb-ft with an early torque peak (~1600 rpm) while still staying on regular. It'll not be a paragon of refinement, but it'll be cost efficient and more fuel economical than a V6.

[regfootball]

anyone think its not just coincidence that they released the EPA figures for the Eco, right about when the IPO may take place?

keep in mind one thing regarding the eco......12.5 gallon fuel tank as opposed to the larger one.....

Edited November 12, 2010 by regfootball

[67impss]

Are you implying that the Government(EPA & Executive branch) are manipulating the IPO process? They are the major stockholders.