Curbside Classic: 1973 Chevrolet Impala Sport Coupe – The Minato Connection

(first posted 2/18/2016)    There are some cars, such as a 1973 Impala, that are pretty likely to interest a sizable swath of readers due to familiarity and first-hand experience.  After spending hours in preparation of an article, realizing you’ve struck a happy chord with the audience is gratifying.

However, on the flip-side, there are some cars, such as a 1973 Impala, in which there isn’t much original that can be said about it.  Model year 1973 wasn’t the beginning of a bold new generation of Chevrolet, there aren’t any mind-blowing technical innovations found within it, nor did it earn a whole host of positive accolades in its day.  For me sitting at a keyboard, that poses enough of a problem to facilitate my letting these pictures ferment for several years.

Sometimes it’s great to learn you are wrong.

Many of us, which is likely a sizable number after 43 years, were too young to have first-hand experience with these.  Being a very small infant when the 1973 models were introduced, I’ve tended to gravitate toward other, celluloid associations with the 1973 Chevrolet.  Don’t get me wrong; I have seen oodles of these on the road in my lifetime, but they were getting some age on them before I became aware.

mcq impala

The first 1973 Impala that came to my mind (after the one belonging to old Mrs. DeWitt, the retired local school teacher) was from the 1974 John Wayne film, McQ.

This movie has the distinction of being the first to use a black powder cannon to flip a car without using a ramp.  Once upon a time, a car stunt in a movie did not necessitate computer animation that thumbed its nose at the laws of physics.

If you want to see how this turns out, here’s a clip of a Plymouth (driven by 67 year-old police officer Wayne), a Chevrolet, and a Cadillac frolicking on the beach.  In a grand salute to 1970s style, two of these cars are green.

live and let die impala

However, from various comments I’ve read here over time, a movie long associated with this vintage of Chevrolet would be the James Bond film, Live and Let Die.  Chevrolet produced 941,000 full-sized cars for 1973 and about half of them seem to have made their way into this movie as every car between New York and Louisiana was a brand new big boned Chevrolet.  Ah, the beauty of product placement.

So while production of the big Chevrolet was down about 75,000 units from 1972, there was a time not that long ago when a person couldn’t sling a dead cat without hitting an Impala (or Caprice or Bel-Air).  In a sense these were the Toyota Camry or Honda Accord of the day; simple, reliable, straightforward transportation for those who needed something to ferry folks around.

1973 belair taxi

There are even similarities in their variety of uses; lots of folks rode in a Bel-Air taxi….


Much like many people these days have ridden in a Camry taxi.

accord taxi

Far fewer Accord taxis are to be found.

Yes, I really like that shot of the Bel-Air taxi and looked for an excuse to include it; think of these taxi shots as being gratuitous, much like nudity or violence is in many movies.  Any car that can hack being used as a taxi is worthy of recognition.

Over time the Impala (or the full-sized Chevrolet in Bel-Air, Impala, and Caprice guises, if you prefer) weaved its way into the American lifestyle of the 1970s – and beyond, as I will occasionally still see one of the big B-bodies on the road that does not have 38″ rims.  Size be damned; people liked these cars.  If you think the Camry (and Accord) is popular now, just remember the Camry’s sales volume for 2015 was roughly half of the 1973 full-sized Chevrolet sales tally.

Granted the market was different then, but hopefully the visual appeal is evident.  How often do you see a two-door car that looks so relatively lithe in spite of its 121.5″ wheelbase?

If only the output of the components under the hood worked to continue the windswept sheetmetal encapsulating it.  1973 was the last and (thankfully) final year one could order a straight-six in their full-sized Chevrolet until the downsizing in 1977.  Cars were becoming heavier – a Sport Coupe such as this had a curb weight of 4,096 pounds, presumably dry – and engine power was down.  The numbers showing power rating were reduced due to a change in measurement in 1972 but actual output was also down to meet ever tighter emission standards.

The four-barrel 350 cubic inch (5.7 liter) V8 found in this particular Impala was rated at 175 horsepower – about ten less than a 2016 Honda Accord.  A mere three years earlier in 1970, that same configuration of 350 was advertised at 300 horsepower.

Emissions and safety equipment were the defining factors in cars during this time, and the implementation was not free from significant growing pains before it matured.  However, when looking at the 1973 Impala from this pubescent angle, the story really begins to blossom.

Such as discovering who was one of the most unlikely buyers of one.


So what in the world does Soichiro Honda have to do with a 1973 Chevrolet?  He is that unlikely owner.  Not only did he buy a 1973 Impala, he had it air-freighted to Japan.

With the emission standards for 1975 looming over the heads of manufacturers in the United States, there was a lot of angst on how to best meet these requirements.  In a sense, this isn’t vastly different than how diesel engines in the trucking and off-road markets have had the tiered approach the last several years to ease into emission standards.


Honda had developed their CVCC engine system in 1971, allowing them to initially meet emission standards without having to resort to using heavy and costly catalytic convertors.  Hedging their bets, Ford and Chrysler became licensed with Honda to produce this system if needed.

The CVCC engine system was pretty ingenious.  Putting a rich mixture into a chamber near the spark plug, yet outside the cylinder, combustion took place in this chamber and carried over to a very lean mixture in the cylinder itself.

richard gerstenberg

When the CVCC engine was introduced in 1973, then GM president and CEO Richard Gerstenberg flippantly dismissed the technology.  In a statement that was a twenty-one gun salute to both short-sightedness and plain old arrogance, Gerstenberg stated:

“Well, I have looked at this design, and while it might work on some little toy motorcycle engine…I see no potential for it on one of our GM car engines.”

This understandably didn’t sit well with Mr. Honda.  In one of the more polite and professional ways of saying “kiss my ass” found in modern history, Mr. Honda purchased his 1973 Impala and had his engineers get to work.  They adapted its 350 cubic inch V8 to CVCC technology by installing a custom made intake manifold and cylinder heads while maintaining the factory four-barrel carburetor but discarding the EGR valve.  Sending the car back to the United States, Mr. Honda then had the EPA test it for its emission levels.

The Chevrolet had 3,000 miles of testing upon reaching the EPA’s laboratory and it retained its factory levels of power output.  The only difference was peak horsepower was reached about 300 rpm sooner than when it left the factory.

EPA 73 Impala CVCC

Subsequent to testing, the EPA released a full report about the CVCC Impala.  One of the more enlightening tables can be seen here.

In their conclusions, the EPA generally had favorable comments, stating the use of CVCC technology did indeed allow full-sized cars to reach emission standards for 1975 and 1976.  This was able to be achieved without exhaust gas recirculation (EGR), which they found satisfactory.

The only real flaw to be found is seen in this table.  Both NOx and CO2 emissions were higher with the CVCC engine, but overall the engine was cleaner burning than in stock configuration with fuel mileage comparable to other cars with similar weight and engine displacements, as per elsewhere in the report.  The various statements and results about fuel economy found in the report do conflict each other.

How the EPA figured a stock 350 Impala could obtain 18 miles per gallon at a steady 60 miles per hour is unknown.

When I took these pictures in 2013 I had no clue about any of this.  All I knew was this Impala Sport Coupe belonged to one of the two mechanics who worked to refurbish my old Ford Galaxie.

Sadly, I forget the gentleman’s name (although I clearly remember his face), but he has owned this Impala for quite a while.  It’s been the car he’s driven to work for years and it belonged to his mother before him.  He had no clue how many miles had accumulated on the odometer.

So I suppose I shouldn’t be so quick to hesitate about a car due to a perceived lack of information.  Sometimes the biggest goldmines are in the most ordinary pastures.