The reason American cars have such huge
engines begins with the nature of America itself. First of all, America is a large country, rich in
natural resources. As strange is this may seem today in the era of
OPEC it should be remembered that America spent the first half of the
Twentieth Centrury as a net
exporter of
petroleum. Petroleum exploitation began in the hills of
Pennsylvania and later in
Texas. That explains why US
oil companies are everywhere. The American
automobile industry sprang up in a climate not far unlike that of the
Gulf States. Once people get used to low prices for something it becomes a
political problem when that luxury goes away.
The fact that America retains substantial domestic oil reserves and domestic production of its own makes the U.S. less vulnerable than it might be to oil price shocks. America is still vulnerable, but what hits the US is felt by everyone. The perception of vulnerability is simply not so strong as elsewhere, and probably not as strong as it ought to be.
Second, America is a big, new country with a rather small population. If you look at a world population density grid you will see that even in the relatively populous states east of the Mississippi River, the U.S. population rarely exceeds 25 or 50 per square kilometer. In Europe 250 to 500 is more typical. in some highly urbanized parts of the world the number may exceed 1,000 per square kilometer. Such numbers are atypical in America, except perhaps in New York City. Because American cities had room to grow, they grow out rather than up, and expansion includes planning for traffic.
The youth of America affected how our cities grew.. Few American cities are over 300 years old. I have seen graves in Amiens, France older than Jamestown. Europe and Japan have significant historical and architectural legacies stretching back to medieval times. They have also had more wars. Cities were often fortified for protection from bandits and armies so late as the Thirty Years War. History has left much of Europe with exceptionally narrow streets that are challenging to navigate in a Ford Focus, much less a Cadillac Fleetwood. Some American alleys would be streets in Europe. Many American cities were small towns when Henry Ford introduced the Model T. We grew up around the car, not the knight.
Simply put, we have more space than Europe and that leaves more space for parking, wider roads, and more travel lanes with less sacrifice. This greater space means that there is more space to absorb the pollution from a single vehicle, making problems less marked. This means there is less incentive to address them, particularly when such actions would affect the luxuries Americans are used to. it is politically very diffiuclt to advocate conservation without an apparent crisis, such as in 1973 and 1978.
With wide streets, plenty of parking and cheap gas combined with low population density it's easy to see why American cars and motors are large.
Tax policy also contributed to the relative size of America cars. America has very low fuel taxation compared to Europe or Japan. The fuel taxes collected fund highway construction. This is not an accident. When automobiles were first developed, all car engines were big. They had to be, as early internal combustion engines weren't terribly efficient. And in the early days of the automobile, when cars were a luxury item, there was no real social costs associated with what were curiosities.
But at the end of World War II many things changed. Europe and Japan were devastated, America was not. Exporting the tooling required to rebuild a war-stricken world earned the average blue collar worker a good living. But Europe was faced with rebuliding. Heavy petroleum imports would suck away funds better used for the reconstruction And if Europeans drove cars so often as Americans congestion would overwhelm the continent. America, with all its space, still produces some monumental traffic jams. If Europeans drove like we do, the continent would become a parking lot.
So a tax structure was crafted to discourage that sort of consumption. Fuel taxes were kept high as automobiles were treated as a luxury. From the point of view of European governments, the benefits in reduced fuel consumptions was matched by a steady source of income they desperately needed. America has some luxury taxes, but they are minimal and a one time event. In many countries, cars were taxed annually, and the amount of the tax increases with engine size. For example, in France cars were taxed according to the number of "cheval" (horses, or horsepower), which is why France's most enduring car is called the "deux chevaux". Other taxes varied according to literal displacement. If the tax increases substantially above 2.0 liters, then a lot of cars will have 2.0 liter engines. Displacement restrictions also encourage car makers to develop very high tech, multi-cam engines that rev high, because that is the only way to get more power out of a fixed displacement. in America, designers were always free to simply increase the size of the hammer. And the sledgehammer approach really works. then and now. In 1950 Brooks Cunningham bought a Cadillac Deville, added an extra carburetor, signed up Miles and Sam Collier to drive it, and finished ninth at Le Mans. Today the Dodge Viper and Z06 Corvette regularly outrun cars that cost more than double their price.
Without tax, economy or regulatory reasons to limit the size of American car engines, the industry incentive to go to smaller motors was zero. Big motors are fun. Small motors can produce real power, but only at high RPM. Big motors produce big power right now. They produce loads of torque at very low RPM. In fact, they produce lots of torque at almost any RPM. If you drive one, you'll like it. Trust me.
Hence, the big motored American automobile or SUV is less a product of a peculiar American character than a natural consequence of the different conditions found here.
America's low population density explains why public transportation in America is so bad by Japanese or European standards. In all but the very largest of American metropolises public transport is so bad as to render the automoble not a luxury, but an economic necessity.
Let me offer an example. I live in Columbus, Ohio and have a friend who was involved with a reorganization of our local bus system, known as COTA. A consultant was brought in to rationalize the city's bus routes. He laid out his maps and began with the statement: "assuming a population density of 200 per acre."
As we have seen earlier, such numbers can readily assumed in much of the world. But not in Columbus, even though by population it is the 15th largest city in America. My friend informed the consultant the population density inside the city limits was typically around 40 per acre, sometimes 20 and only approached the assumed 200 in a very few neighborhoods. In my neighboorhood of small, working class homes, the 20 number applies, and we aren't rich.
This means America is very spread out compared to much of the world. So if a bus must have 20 passengers aboard to pay for itself, and the percentage of people wanting to go somewhere is the same in both Europe and America, then the average American will have to walk much farther to catch said bus. Or the bus will have to pass by much less often. Both further discourage riding. This leaves Americans with a simple choice. Heavily subsidize a generally underutilized public transportation system. Or see commute times increase, often by a factor of ten or more. The long commute times itself constitutes a barrier to employment.
For example most bus routes run to and from downtown because these are the routes where the bus sytem makes money. Downtown is the only place where parking and traffic penalties are high enough to induce well-heeled people to ride. Therefore downtown routes are fairly efficient, and useful. But most low-paying jobs are not downtown. A worker needing to travel to an adjacent suburb, often must go downtown first and then back out to the adjacent suburb. This can turn a ten minute drive into a two hour off-peak commute, including transfers. That can turn an eight hour work day into a twelve hour marathon. Imagine the effect that can have on child care costs and availability. It is also a barrier to employment. And if you don't have work, how often are you going to take a three hour ride to put in a job application before you get discouraged?
America's low population density has significant economic implications, particularly for the poor and working class. Limited public transportation often impedes their progress out of poverty. Automobiles are expensive to operate, and the necessity for reliable transportation sucks income that could be used for other things, like books, the internet or even decent housing. America's dependence on the car renders the working poor extraordinarily vulnerable to mechanical breakdown.
In America, the choice is often drive or stay home. That means we keep cars on the road that are falling apart, creating further pollution and safety hazards, because many people simply have no other good choice. It also makes our economy far more vulnerable to oil price jumps than many other countries. Remember that once you own a properly maintained automobile, the costs of driving a few additional miles are quite low. In fact, the more you drive the cheaper costs per mile go.
For a sample population distribution see http://sedac.ciesin.columbia.edu/plue/gpw/index.html?main.html&2
US cities are ranked at http://www.infoplease.com/ipa/A0108676.html