It's a regular and recurring theme in comments on Green Car Reports: "Yeah, maybe the new 2016 something-or-other gets 31 mpg combined, but so what? My 20-year-old Geo Metro gets 40 mpg and I've put 280,000 miles on it! New cars are all stupid!"

When we have the time or inclination, we often respond that a 1980s or 1990s econobox can't be compared straight across to a modern subcompact or compact car.

Then we lay out the reasons.

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The latest such claim, surprisingly, comes from Hemmings Motor News, the bible of collector-car aficionados throughout North America.

Ten days ago, an article on its blog suggested that, "Forty years later, the Chevette can still get better gas mileage than many new cars."

Which is undoubtedly true. The Chevette gets better gas mileage than, say, a 2015 Cadillac Escalade ESV with four-wheel drive, which is EPA-rated at 16 miles per gallon combined.

2016 Chevrolet Spark, 2015 New York Auto Show

2016 Chevrolet Spark, 2015 New York Auto Show

But we think that to the uninformed, it's bordering on deception to suggest that the Chevette is comparable to a modern car in anything other than having four wheels, space inside for people and cargo, and an engine powering two wheels.

That 1976 Chevette could not legally be sold today as a new car.

It wouldn't come close to meeting today's far tighter tailpipe emissions standards.

ALSO SEE: 2015 Ford Focus 1.0L EcoBoost: Gas Mileage Review

And its safety ratings--now based on crash tests both by the National Highway Traffic Safety Administration and the Insurance Institute for Highway Safety--would be so catastrophically bad that they alone would likely make it a market failure.

Not to mention that its level of standard equipment is far below the minimum required in today's market.

And the performance? Well, a base 1976 Chevette had a 0-to-60-mph acceleration time of 19.6 seconds--which would be dangerously slow and unsafe as a new car.

2014 Ford Fiesta EcoBoost SFE, Catskill Mountains, NY, Jun 2014

2014 Ford Fiesta EcoBoost SFE, Catskill Mountains, NY, Jun 2014

There's still an appetite for small, basic, inexpensive cars, as witnessed by the startling success of the Mitsubishi Mirage mincar and the Chevrolet Spark.

Mitsubishi has now sold twice as many Mirages as it expected to, and Chevy's Spark sales have exceeded their projections as well.

The Mirage, meanwhile, is rated at 40 mpg combined by the EPA. That's the highest rating for any non-hybrid vehicle sold in the States today.

MORE: Strong-Selling 40-MPG Mitsubishi Mirage To Get Sedan Model

And that's better than the best Chevette. Hemmings quotes the gas mileage of the 1976 Chevette as 28 mpg city, 40 mpg highway.

Unfortunately, it neglects to note that those figures would have been adjusted downwards using the modern formulas by which today's cars are rated.

For 1984, the first year in which rates any Chevette models, the best is a diesel Chevette at 36 mpg combined. The gasoline Chevettes--all that were available in 1976--run from 24 to 27 mpg combined.

2014 Mitsubishi Mirage ES - Driven, April 2014

2014 Mitsubishi Mirage ES - Driven, April 2014

Not that impressive after all, eh?

And even the most basic model of either car has standard equipment that no Chevette buyer even dreamt of. And the safety ratings? They're at least acceptable, if not top-notch.

In other words, cars have progressed quite a lot in four decades--despite costing roughly the same or less in real dollars.

We think that's a good thing.


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