The Ford Model T is famous as the car that put America on wheels, and a key element in its success was the remarkable engine.

We don’t think of the Model T Ford engine as terribly advanced or sophisticated. That’s no doubt due to the fact that by the end of the car’s production life in 1927, the powerplant was well past its prime. But when the Model T was introduced in October of 1908, its engine was the state of the art, and it established a number of trends that the auto industry would soon follow. We can start with its basic construction.

An inline four with a bore of 3.75 in. and a stroke of 4.00 inches, yielding a displacement of 177 cubic inches, the T was a rather straightforward design. But its construction was remarkably novel for the time, built upon on a single iron cylinder-block casting (aka monobloc). At the time, most engines employed an aluminum crankcase with separate cast-iron cylinders, poured individually or in pairs, that bolted on top, creating an expensive, complicated, and somewhat rickety assembly.

In contrast, the Ford monobloc casting was simple, rugged, and cheap to manufacture. The Model T also employed a one-piece detachable cylinder head—again, much easier to manufacture, and to service in the field. One more benefit was that the L-head valvetrain mechanism was almost completely enclosed, shielded from road dust and dirt, and after 1911 it was sealed off altogether with a pair of side covers. But it was the monobloc, detachable-head engine construction, in large part, that allowed Ford to manufacture cars in unprecedented numbers at extremely low cost.

Designed, like the rest of the automobile, by Henry Ford, C.H. Wills, Gene Farkas, Joe Galamb, and crew in a secured room at one end of the Piquette Avenue plant, the Model T’s engine was downright sophisticated in its simplicity. There was no water pump (coolant circulated via thermosiphon) or fuel pump (gravity feed) and meanwhile, the engine and transmission were unitized, another advanced feature for 1908 that further enabled high-volume production. The pedal-operated, two-speed planetary transmission itself was not terribly unusual for the time, but it was far simpler for beginners to operate than a balky, unsynchronized manual gearbox of the era. Power was rated at 22 hp, which doesn’t sound like much now but was fairly sporty for the road conditions of the day and allowed the Model T to top 40 mph.

One more remarkable feature that remained throughout the Model T’s production life was its ignition system, another marvel of simplicity—among other things, it required no battery. A low-tension magneto built into the flywheel (in modern terms, we could think of it as an AC generator) supplied a primary current (5 to 32 volts, varying with engine speed) to four vibrator coils, one for each spark plug and cylinder.

While this setup would be utterly unrecognizable to a modern-day mechanic, it could tolerate an almost infinite amount of wear and misadjustment and run nearly forever.  The ignition design was one more element in the fascinating paradox of the Model T:  One of the cheapest cars on the market was also one of the most reliable. And on these two winning attributes, 15 million cars were sold and an entire nation was put on wheels.