Car Engines

Asked which motor they preferred in a car, visitors to the first-ever National Automobile Show in New York city made the electric their overwhelming choice. Steam engines came in second. and trailing the field with less than 5 percent of the vote was the gas engine, which one critic predicted would never last.

"Noxious, noisy, unreliable, and elephantine, it vibrates so violently as to loosen one's dentures. The automobile industry will surely burgeon in America, but this motor will not be a factor," he wrote.

Others attending the show cited an additional reason for their displeasure -- fear that these multi-fuel power-plants (they ran on stove gas, kerosene, naphtha, lamp oil, benzene, mineral spirits, alcohol, and a relatively new fuel called gasoline) would explode and shower them with shrapnel and flame. Show officials increased the public's anxiety by summoning a standby bucket brigade whenever an engine was cranked. The year was 1900.

Four-stroke internal combustion engines

In 1903, to the surprise of most automobile observers (except those directly involved in engineering), a sharp rise occurred in the number of new cars outfitted with  gasoline engines. By 1910, steam engines virtually disappeared as a vehicle powering agent. Electric motors hung on until 1915.

Forty years before and 20 years after the turn of the twentieth century are now known to have been the Golden Era in the development of the automobile gas engine. During this 60-year span, most concepts relative to gasoline engine development were conceived. Engines that have come along since have been refinements of those concepts, which awaited some technological break-through -- either in fuel technology, metallurgy or machine tooling -- to attain reality.

Two-stroke

In 1860, Etienne Lenoir of France invented the first four-wheeled vehicle to be powered by a gas engine. It was a two-stroker that employed two concepts which are considered by some today as new -- stratified charging of the fuel mixture by introducing air and gas separately into the combustion chamber, and water injection. Both methods were employed by Lenoir to keep his one-cylinder engine from knocking.

V8 & V6

In 1906, Cosmopolitan magazine published a complete guide to the new "Gasoline Motor Cars." Thirteen models had one-cylinder engines. 54 had two-cylinder engines, five were equipped with three-cylinder engines, and 59 sported four-cylinder engines.. The remaining vehicles included one with a V8 engine built in Redondo Beach California (it was called The Coyote), and a 40-hp, six-cylinder engine in a five-passenger car. The latter vehicle which sold for $2500, was manufactured by a motor company out of Detroit called Ford. It did not sell and was abandoned after two years.

Although the typical gas engine at the turn of the century was quite different from today's engines, most modern power-plant technology had been tried by 1906. For example, the first en-bloc engine (one-piece cylinder block) had been made in 1896 by Charles B. King, but not even by 1906 had machining techniques reached a level that allowed such an engine to be manufactured inexpensively. Therefore, combustion chambers in the typical multicylinder engines were cast individually and bolted to the crankcase.

T-head & L-head

In 1906, science had not yet perfected a gasket capable of forming a seal between cylinders and cylinder heads. Thus, each cylinder had to have its head cast integrally, with intake and exhaust valves set in caps that were screwed into each head. They named this setup T-head, because the valves straddled the piston.

Each set of valves was operated by its own camshaft. The two shafts -- one for intake valves and one fore exhaust valves -- were located in the crankcase. They pushed up on long stems that lifted the valves off their seats. As the cam lobes moved off the valve stem tips, heavy springs caused the valve to slam shut.

Since the material that the valves were made of was relatively soft, this gave rise to a particularly bothersome situation. Valve life was numbered in hundreds of miles. But car manufacturers had a way around this -- they equipped new vehicles with a spare set of valves! When a person got stuck at the side of the road, he unscrewed the valve caps from the cylinder heads to replace the damaged valves.

Overhead-cam

The T-head engine gave way to the L-head (also called the flat-head or side-valve) engine in which valves were placed on one side of the engine. The L-head dominated the scene for years. Ford used it on V8s until 1953. But waiting in the wings was another design, introduced in 1898 by Wilkinson Motor Car Co. -- an engine that had the camshaft and valves in the cylinder heads. You know it as the overhead-cam (ohc) or overhead-valve (ohv).

Air-cooled engines

During this Golden Era, other notable innovations bearing on the development of the gasoline engine took place. The engine in the 1905 Knox was a horizontally opposed power-plant similar in makeup to one adopted 30 years later by Volkswagen for use in the Beetle. Like the Beetle engine, the Knox engine was air-cooled. Corrugated pins surrounding the cylinders made it possible to obtain 32 square inches of heat radiating surface per square inch of outside cylinder surface.

Another noteworthy car was the 1906 Premier, with a four-cylinder vertical engine. It had a 4.25 x 4.25 inch (108 mm x 108 mm) bore and stroke, making it one of the earliest "square" engines. As late as 1953, C. F. Kettering, automotive genius and inventor of the electric self-starter, wrote: "The so-called square engine with the bore more nearly equal to the stroke in order to reduce piston speed brought us a considerable way down the path to the modern engine." He was referring to engines in the 1949 Cadillac and Oldsmobile.

Engine placement

The early innovators were not adverse to shifting the engine from place to place. At first, it was put under the front seat. Then, it was moved under the hood. Some think it was not placed in the rear until VW did it with the Beetle. Surprise! in 1896, a car called the Hertel had an engine back there.

Most people today are familiar with front-wheel-drive (fwd) cars. Many probably think it is a new concept. Wrong! In 1900, the Pennington Car co. came out with a vehicle that had a gas engine driving the front wheels. This was not even the first fwd car. Electrics and steamers had been using fwd for years.

Ford Model T

Coverage of this period would be incomplete without mentioning the 1908 Ford Model T, or Tin Lizzie. Its four-cylinder 20-hp engine was the first mass-produced, inexpensive power-plant to be en-bloc with an individual cylinder head. Perfection of a copper-asbestos head gasket was one of the key developments making this possible.

Engineers knew for a long time that they could theoretically design more efficient engines by increasing compression ratios. By squeezing the fuel mixture into a smaller combustion space before it was ignited, smaller, more powerful engines could be used. However, every time this was tried, engines reacted violently, knocking terribly. The problem was not the engine, but inadequacy of the fuel. So, until the mid-1920s, compression ratios of engines in cars sold to the public ran no higher than 4.3:1.

Increased engine efficiency

That limitation ended in 1923 when tetraethyl lead and improved refining methods gave gasoline antiknock qualities. This development allowed engineers to try certain mechanical improvements that increased engine efficiency still further without fear of knocking. Some of these improvements included redesigning combustion chambers, using differently shaped pistons, and bringing spark and valve timing into greater focus to attain maximum fuel combustion.

The search for better materials to withstand the increasing stress of higher speed engines became critical as more paved roads became available.

In the early days, when there were a limited number of dirt roads, heavy iron engines that lumbered along were met with little resistance by the automobile buyer. However, as more roads were opened to drivers and road conditions improved, driving became more popular and demand increased for lightweight engines that could take travellers longer distances economically.

Start of the automotive metallurgical industry

The man who had most to do with the start of an automotive metallurgical industry in the United States was Elwood Haynes. Among his accomplishments were the development of cobalt, chromium and tungsten alloys; discovery of stainless steel; and introduction of aluminium into automobile engines.

Rotary engines

In 1893, Haynes invented and built a rotary gas engine. Did you really think Felix Wankel was the first to do this in 1955?

In 1912, an ad for the Type 35 Mercer, which sported an in-line six- cylinder engine, made mention of a "large and perfectly balanced crankshaft to make the engine practically vibrationless." The Mercer Automobile Co. recognized that as low-speed engines gave way to high- speed engines, vibration caused by crankshaft rotation was going to become troublesome.

Vibration dampener

Balancing the crankshaft became even more of a factor as the number of cylinders increased. In 1916, Packard introduced the first production 1 2- cylinder engine. To quell the effect of crankshaft vibration, Packard placed a small flywheel on the front end of the crankshaft that "slipped," as necessary, to help smother torsional vibration produced by the shaft. This we now call a vibration dampener.

Refining crankshaft balancing

Cadillac refined crankshaft balancing still further. On its 1923 V8 engine, the company arranged the four crankshaft pins in two planes to balance out the vibration effects of the reciprocating pistons and connecting rods. The four-crankpin arrangement, like the vibration dampener, is still with us today, but they probably played their most important anti-vibration roles in the early 1930s, when some car companies strived to have an engine with the most cylinders. For example, there were the Cadillac, Marmon and Packard V16 engines and the Lincoln V12.

By 1934, public interest in these massive power-plants started to wane, leaving six- and eight-cylinder engines to reign for almost 50 years. Today, the Four has returned and now it looks like two- and three-cylinder engines may make a comeback. In other words, we've gone from the one-cylinder gasoline engine to 16 cylinders and back to four. Is the return of the one- cylinder only a matter of time?

"Firm offers two models of high-speed motor with twin intakes and exhausts." This is not an ad for a modern Toyota 16-valve engine, but the way Automobile Topics described the four-cylinder, four-valve car engine made by Linthwaite-Hussey Motor Co. of Los Angeles. The year was 1916.

"The most marvelous automobile improvement yet invented," another ad says. "Pull the little lever -- your 12 is a 6; push the little lever, your 6 is a 12." This was the way the Enger Motor Car Co. of Cincinnati described the 1917 Twin-Unit Twelve. By means of a small lever on the steering column, the driver was able to cut out six of the engine's 12 cylinders to attain maximum fuel economy, and cut them back in just as quickly for maximum power.

The lever pulled the exhaust valves off their seats, so there was no compression in the cylinders. It also allowed a shutter to close the intake manifold feeding fuel to those six cylinders.

Are you surprised to learn that the 1981 Cadillac V8-6-4 engine wasn't the first that could have the number of its cylinders regulated? If so, get ready for another surprise. Neither was the 1917 Enger. The distinction belongs to the Sturtevant 38- to 45-hp six-cylinder engine of 1905. Three of its cylinders could be shut down.

Hemihead engines

Another gasoline engine development worthy of mention is the 1924 Chrysler six-cylinder L-head, which incorporated a hemispherically domed combustion chamber designed to combat detonation, and the first replaceable cartridge oil filter. But don't get the idea that this was the first hemihead engine. It wasn't. As far as we've been able to determine, that distinction is reserved for the 1904 Welch Four.

Another car of the 1920s worthy of mention was the 1926 Cadillac V8, which introduced crankcase ventilation to get rid of contaminating agents that caused engine wear. This vent system, open to the atmosphere, continued until 1963 when positive crankcase ventilation (PCV), a closed system came into use.

Many engines of the 1930s introduced exhaust-valve seat inserts to overcome burning and pitting, hydraulic valve lifters and lightweight Babbitt metal bearings that were able to handle loads imposed by higher and higher engine speeds. And 1949 saw the introduction of lightweight, square bore-and-stroke, ohv, high-compression V8 engines by Caddy and Olds.

The future

What of the future? What will gasoline engines be like? Let's quote one of the most renowned auto experts: "With higher compression ratios, improved transmissions, new materials, new manufacturing techniques and so on, you can practically draw your own picture of the engine of tomorrow: smaller, lighter, more reliable, smoother and 50 percent more economical."

The expert was Kettering. The year he made his prophecy was 1953. And if he were alive now to speak about the engine of the future, he would probably say the same thing.

© Used Cars Australia Sydney, Brisbane, Melbourne, Canberra, Adelaide, Perth, Darwin & Hobart Australia