Toyota YarisClick to enlarge picture

The Toyota Yaris is one of the most efficient vehicles on the road today but it would be no match for the Geo Metro 15 years ago.

Yep, gadgetry has gotten smaller, faster and more versatile but has the technological juggernaut had that much impact on the cars we drive?

One has to surmise that the advancement of computer-chipped electronics has had an impact on automotive ECUs. And it has. Today's engines are making more power from less displacement than ever before and doing so while generating minute traces of emissions.

Extrapolating that tuning success to fuel economy seems like a logical progression; but don't go all-in with this bet. Looking back 15 years reveals that the fuel mileage evolution has stagnated, even regressed to Neanderthal-esque standards in some cases.

The fuel mileage saga is spelled out in the MPG Super Stars chart. Five 1992-vintage cars outperform the best gasoline-powered offerings from 2007 while a sixth equals them in highway mileage.

The Geo Metro XFI and Honda Civic VX produce hybrid-challenging numbers. The Metro tops the chart at 53 city, 58 highway while the Civic VX is right on its heels at 48 city, 55 highway. Both Metro XFI and the Metro LSi (also offered as the Chevrolet Sprint in 1992) are small, lightweight vehicles motivated by a 1.0-liter, three-cylinder powerplant.

There is no doubt that these GM hatchbacks lack the creature comforts and build quality of modern econoboxes and at 49 horsepower, they are not inspiring performers. Conversely, the Civic VX was a new, fresh-sheet car in 1992 with highly rated ergonomics, excellent build quality and more than twice the pep of the XFI at 102 horsepower. Despite their shortcomings for the environmentally conscious, these misers are indeed super stars.

MPG Super Stars [city/hwy]

1992 2007
Geo Metro XFI ('93) 53 / 58 Toyota Yaris 34 / 40
Honda Civic VX 48 / 55 MINI Cooper 32 / 40
Geo Metro LSI 46 / 50
Suzuki Swift 39 / 43
Ford Festiva 35 / 42
Dodge Colt ('93) 32 / 40

Under the banner of, "the more things change the more they stay the same," we present the Super Suckers. The worst fuel mileage vehicles on the road have evolved little in the last decade and a half. The Lamborghini Diablo of 1993 and the present day Lamborghini Murcielago both have V12 power and the same woeful 9 city, 14 highway performance.

The Vector W8 was a low-volume specialty car that did not stay in the market very long but it did take the title of least fuel efficient. Granted buyers of these rides care little about their daily fuel consumption and these supercars are not driven all that much but you would expect Lamborghini could at least nudge the needle in right direction 15 years later.

MPG Super Suckers [city/hwy]

1992 2007
Vector W8 7 / 11 Lamborghini Murcielago ('06) 9 / 14
Lamborghini Diablo 9 / 14 Bentley Arnage 10 / 15
Mercedes-Benz 600SEL 11 / 15 Bentley Azure 11 / 16

The meatiest comparisons focus on the same make and model of car in 1992 and 15 years later in 2007. The most shocking of the apples-to-apples showdowns is the Honda Civic. In the last 15 years the Civic has given up ground in a big, nearly unimaginable way; dropping 12 MPG city and 8 MPG highway. How is this possible? The four-cylinder engine has grown from 1.5-liters in '92 to 1.8-liters in 2007. But come on, engine displacement is not the issue, overall displacement, read curb weight, is.

Just as Americans have embraced obesity, the lowly Civic has gone from 2094 pounds in 1992 CX hatchback trim to 2751 pounds in 2007 sedan trim; the additional 657 pounds of girth in the '07 version will certainly make efficiency numbers plummet. Calculating a sedan versus sedan comparison reveals the 1992 edition to be 432 pounds lighter on the scales.

It should be noted that there were a wide variety of Civics offered in '92. In addition to the aforementioned VX, seven other Civic models delivered between 27 and 42 mpg in the city and 34 and 48 mpg on the highway.

The Nissan Sentra is even-up when looking at city mileage and minus three in highway performance. The 1992 car runs a 110-horsepower 1.6-liter while the 2007 version relies on a 140-horsepower 2.0-liter engine. And the current edition needs that thrust since it tips the scales 586 pounds heavier than its 1992 brethren.

The remainder of the comparisons, even the pickup trucks, show stagnation or mediocre improvement in fuel economy over the years. The Chevy C1500 has evolved into the present-day Chevrolet Silverado 1500.

15-Year Flashback, Same Model Comparison [city/hwy]

Vehicle 1992 2007 Difference
Honda Civic 42 / 48 30 / 40 -12 / -8
Honda Accord 24 / 30 26 / 34 +2 / +4
Nissan Sentra 29 / 39 29 / 36 0 / -3
Toyota Corolla 31 / 35 32 / 41 +1 / +6
Toyota Camry 22 / 29 24 / 34 +2 / +5
Chevrolet Corvette 17 / 25 18 / 28 +1 / +3
Ford Explorer 4WD 15 / 19 15 / 20 0 / +1

Vehicle 1992 2007 Difference
Dodge Dakota 4WD V8 5.2-L 13/17 4.7-L 15/20 +2 / +1
Chevrolet C1500 2WD V8 5.0-L 15/20 5.3-L 16/21 +1 / -1
5.7-L 14/18 6.0-L 14/19 0 / +1

With all the drum beating about oil reliance and fuel conservation as America watched crude prices soar past $72 a barrel in April, 2006 it is a bit sobering to see how little progress has been made in extending miles per gallon. There are variables at work against fuel economy today; increasing engine sizes and the expanding girth of the vehicles that are bigger and weighed down with more commuter-friendly accoutrements as well as advanced safety equipment. It is worth mentioning that equipment was added to meet buyer demand as well as government regulations. Also, the driving experience in a Metro XPI cannot compare in any way to that in a Toyota Yaris.

But in many ways the Yaris and its counterparts in the emerging B-Segment of vehicles are throwbacks to the misers of the early '90s. The B-Segment consists of the Yaris, Nissan Versa, Scion xA and xB, Honda Fit and Suzuki SX4. The all-new Japanese market Mazda Demio that will be rebadged as the Mazda2 for U.S. consumption and delivered our shores in 2008 may join the micro-car party. B-Segment cars are fuel-efficient, clean-burning and defy their diminutive proportions when comes to accommodating cargo and people.

If the main factor is fuel efficiency, the truth is things haven't come so far since '92 when Clint Eastwood's "Unforgiven" took the best picture Oscar and Eric Clapton won five Grammy Awards for his "Unplugged" album. With the government mandating higher CAFE standards, especially for trucks and SUVs, one has to think there are some frayed nerve endings in the product planning departments of all the automakers right about now. Whatever unfolds and whatever one's personal preference may be when it comes to fuel efficiency, knowing the history of the beast will ensure tomorrow's buyer makes an informed decision.

From 1992 to 2005 Evan Griffey was an editor of Turbo & High Tech Performance magazine, a pioneering force in the creation of the import/sport compact tuning industry. Today Evan is a freelance writer working for Import Tuner, Sport Compact Car, Honda Tuning, Turbo & High Tech Performance, Car Audio and Siphon magazines.

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