The man who made the most noise about steam, though, was the brash and overconfident William P. Lear of Learjet fame. At a decommissioned military base outside Reno, Nevada, Lear developed several types of steam and steamlike engines. One was what he called an “involute expander,” which used intermeshing helical screws. Another was a 12 cylinder opposed-piston engine based on the British Napier Deltic diesel; the cylinders formed side-by-side triangles. A third was the Lear Vapor Turbine System, which involved a sealed turbine that used not steam but a revolutionary new fluid called Learium. Unfortunately, Learium was never developed.
In October 1973 the Arab oil embargo hit, forcing automakers to turn their attention away from steam to the more immediate challenges of downsizing and making the internal-combustion engine cleaner and more fuel-efficient. They succeeded well enough to put steam out of contention. Despite the progress some engineers believed they were making between 1968 and 1973, steam cars continue to pose seemingly insuperable challenges, principal among them being fuel economy. There’s no promise of future improvement, as there is with electric cars, in which batteries are being made smaller and smaller.