Hearings, Reports and Prints of the Senate Committee on Public Works

FACTORS AFFECTING SELECTION OF THE SPARK IGNITION ENGINE IN 1900 AND NOW

By David E. Gushee, Joseph P. Biniek, and John E. Blodgett, Environmental Policy Division, and Mauree W. Ayton, Science Policy Division

SUMMARY AND CONCLUSIONS

The present day turmoil surrounding the automobile engine and its performance bears many similarities to the turmoil within the "industry" in the early 20th century, when it was making the decisions that have shaped it for the past 50 years. Then, as now, there were a number of newly-important design variables. Then, as now, each type of engineering approach had its champions. Then, as now, the only way to determine the design that would meet all the performance parameters was to experiment in large scale in the marketplace.

The analogy, to the extent it is appropriate, is of considerable help in sorting out the issues involved in today's controversies and in predicting how they will shake out over time. In the beginning, some 20 years of full-scale competition in the market place were required before the spark ignition engine established its ability to meet the performance requirements and to defeat the challengers. Today, with heightened concern for reduced emissions and deep rumblings about the need for fuel economy, the question of relative performance of alternative engines is again raised. But this time, the spark ignition engine is in the saddle; a challenger must be not merely as good-it must in all probability be quite a bit better to justify that cost and trauma of replacement.

FACTORS AFFECTING EARLY DECISIONS IN FAVOR OF SPARK IGNITION ENGINES

The literature of the late 19th and early 20th centuries, as well as more recent studies of that literature and of that period, does not provide the answer to the question as to why the spark ignition engine became the engine of choice. However, that literature does support the following conclusions:

1. At the time of its original selection as the engine of choice, the spark ignition engine had no over-all intrinsic advantage over other types of engines.

2. The spark ignition engine became the engine of choice as the result of a number of circumstances and events rather than as the result of a formal decision-making process. Among the circumstances and events were:

(a) Although steam-powered road vehicles were developed in the 1820's, restrictive legislation in England in force be

(1)

tween the 1830's and 1896 discouraged further developmental efforts during the period of conception and early development of the spark ignition engine.

(b) Henry Ford picked the spark ignition engine to power his cars. When the Model T succeeded, the spark ignition engine was assured of at least a place in the range of auto engines to be used. Why Ford picked the spark ignition engine is not clear, beyond his great concern for light weight.

(c) Once Ford was in mass production, his competitors had to pick a basis on which to compete against him. His most successful competitor, General Motors, decided to compete on the basis of financial and marketing values and not on the basis of engine type.

(d) Standard Oil Co., with its development of the Burton process to crack crude oil, assured a plentiful supply of inexpensive, though "highly refined," gasoline needed by the spark ignition engine but by none of the other types.

(e) Adding the electric starter, which removed the problem (and danger) of handcranking to start the engine, opened the women's market to spark ignition-powered cars. Up to that point, women had preferred the electric car.

(f) When Doble entered into competition against Ford with a steam-powered car, World War I came along, causing the Government to intervene in the interest of war production. Doble did not fill $27 million in standing orders; when the war was over, any momentum for Doble's steam-powered competitor that might have built up was gone forever.

(g) In the early 1920's, when roads were becoming good enough to support a demand for higher engine performance, Midgley discovered tetraethyllead which, when added to gasoline, provided the spark ignition engine with the performance capability to defend its position against the known highspeed performance of the steam-powered engine.

3. As car buyers increased the stringency of their demands for engine performance, the industry successfully modified the spark ignition engine to satisfy those demands. There has been no Achilles heel in its performance on which competitive types of engines could base a challenge.

FACTORS INFLUENCING CONTINUED RELIANCE ON SPARK IGNITION

ENGINES

Fierce arguments raged for a quarter century or more over whether the spark ignition engine, the steam engine, or the electric battery would be the best way to power a car. Reading those arguments today, one cannot help but wonder at the willingness of any entrepreneur to risk his all on any one of them. But at least he didn't have to worry about displacing an engine already performing satisfactorily.

1. In contrast to the situation in 1900, the spark ignition engine today has a fundamental intrinsic advantage over all other candidates. Over more than 50 years, hundreds of millions of them have been made, used, maintained, and repaired:

(a) Massive production facilities, tools, and methods exist for their large scale production.

(b) Designers have an immensely detailed and documented understanding of factors affecting their design, performance, and

cost.

(c) Hundreds of thousands of people are trained in their maintenance and repair.

(d) A network of service facilities, with tools and spare parts distribution, has been built up.

(e) Millions of customers through personal experience have gained confidence in spark ignition engines.

(f) There is incontrovertible evidence that progress is currently being made in designing them to operate at lower emission levels without intolerable sacrifices in other parameters of performance. 2. There are no equivalents in knowledge, experience, or data with alternative engine designs. Thus it is not possible to prove that a change to one of these alternative designs would be beneficial-in either emission reduction or other performance parameters.

3. Reducing emissions is not the only change in engine design parameters that must be incorporated over the next decade. Fuel source, fuel economy, and transportation functions are in process of reconsideration as a result of major shifts in population, social values, and resources. Many of the factors involved in these changing parameters are not yet clear. In light of such uncertainty, decision makers seek to keep open as many options as possible for as long a time as possible or conversely, to make short term decisions as incremental as possible and to postpone major "change" decisions.

4. All technological innovation, including incremental steps, follows a pattern that can be expected to apply to the auto industry. Typically, an innovation is introduced on a small scale, tested, and proved; gradually it penetrates the market. The period of experimentation varies widely, depending on numerous factors, including those listed above in numbers 1 and 2, and involving the complexity of the innovation, the extent of the supporting system for the existing technology, and the social values affected. Several years is almost certainly the shortest period in which a major innovation can fill a market opportunity.

While the process of innovation can be shaped and directed to some extent by legislation, research and development, and investment, there are limits to how much it can be affected.

The issue is not only whether the evaluation period can be shortened, but also, in the light of the long-term changes in the offing, as noted in number 3, and the reductions in emissions from spark ignition engines currently being achieved, whether the evaluation period should be shortened.

tween the 1830's and 1896 discouraged further developmental efforts during the period of conception and early development of the spark ignition engine.

(b) Henry Ford picked the spark ignition engine to power his cars. When the Model T succeeded, the spark ignition engine was assured of at least a place in the range of auto engines to be used. Why Ford picked the spark ignition engine is not clear, beyond his great concern for light weight. (c) Once Ford was in mass production, his competitors had to pick a basis on which to compete against him. His most successful competitor, General Motors, decided to compete on the basis of financial and marketing values and not on the basis of engine type.