Revving Up for the Wankel

In the headquarters of Detroit's automakers, executive desk tops and coffee tables have lately sprouted plastic models of a strange-looking engine, and in high-level conversations around them, knowing mentions are made of something called an epitrochoid. Visitors soon learn that the models are see-through likenesses of the Wankel rotary engine--and an epitrochoid, in case they did not know, is the bloated figure-eight shape that its rotor follows when moving. Both the baubles and the vocabulary are just two more signs that the long-discussed Wankel has finally shifted up from being Detroit's vague "engine of the future" to a much more imminent status. The auto industry's growing number of Wankel watchers, including the authoritative trade magazine Ward's Auto World, an early booster, predict that Detroit will be mass-producing rotary engines in three years or so, and that by the end of the decade, more than half of all new domestic cars will be powered by them.

Coattails. The Wankel revolution has been expected for years, chiefly because of the rotary engine's elegant simplicity. Instead of converting up-and-down piston motion into wheel-driving circular energy through a series of complex linkages--the way a standard engine works--the Wankel rotors spin continuously and thus provide the proper torque to move a car's wheels directly. Rotary engines are smaller, peppier and potentially cheaper to build than conventional reciprocating models, and have only six major points of wear, v. 100 in a conventional engine. The most persistent bug, ever since Inventor Felix Wankel (pronounced Van-kel) introduced his first complete model in 1957, has been a tendency for the rotor tips to wear down too quickly. That problem apparently has been solved with modern metal-coating processes, but the rotary engine still has at least one major disadvantage. It uses about 10% more fuel than standard engines at high speeds, thus adding to consumer costs and in effect wasting an already precious natural resource.*

Detroit's Big Three are pushing extensive, top-secret research projects on the Wankel, and investors and businessmen are already revving up to cut themselves in on the profits. Except for General Motors, which in 1970 bought a license to make Wankels in a deal that will eventually cost it $50 million, any manufacturer who decides to build a rotary engine will presumably have to pay royalties to Curtiss-Wright Corp., which owns North American patent rights to the design. Largely on the strength of that asset, Curtiss-Wright stock shot up from 1 3/8 to 59 1/4 earlier this year, though it has settled back in recent weeks to around 45. Officers of machine tool firms are hoping to produce assembly-line equipment for what could be the biggest car design change ever made.

The boomlet has been helped along considerably by the reception given to the first rotary-powered car available in the U.S., Japan's smooth-riding and exceptionally zippy Mazda (TIME, April 5, 1971). Some 20,000 Mazdas were sold last year, even though the car has been made available in only 20 states. Mazda already ranks as the seventh biggest-selling import. Toyo Kogyo, the manufacturer, has received no fewer than 2,300 applications for some 100 Eastern and Midwestern dealerships that will be awarded this summer and fall.

Toyo Kogyo officials recently surprised other manufacturers by saying that they have "a fairly bright outlook" about meeting federal emissions standards for '75 and '76 models. U.S. automakers have flatly said that those rules, which would reduce by 90% the pollutants spewed out by a 1970 car, are impossibly strict. Mazda's equanimity was apparently based on the fact that Wankel engines operate at temperatures about 10% lower than standard internal-combustion engines do and thus produce fewer oxides of nitrogen, the primary target of the emission standards for the mid-1970s.

Since Detroit's plans for the Wankel are still under wraps, U.S. automakers try to remain noncommittal in public. Occasionally they do not succeed. A top GM engineering executive told TIME Detroit Bureau Chief Ed Reingold: "Just wait until you see our rotary--it's ten times better than the Mazda." And just when might that be? GM officers will not answer, but according to persistent rumors around Detroit, the company will offer rotary engines as an option on '75 Vegas and perhaps a year later on a compact. Most engineers agree that rotary engines will first become available on subcompacts and progress to larger-sized cars.

Yet there is no inherent reason why rotary engines will not ultimately be suitable for any U.S. car. GM is believed to be experimenting with a Corvette outfitted with a rotary engine placed just behind the driver's seat, in the midsection of the car. Because Wankel-type power plants are only half the size of normal ones, Detroit's designers are having a field day trying out rearrangements of a car's basic features. Says David Cole, head of the University of Michigan's auto engineering laboratory and the son of GM President Edward Cole: "The rotary is going to help make the automobile a totally different vehicle ten years from now."

Love Affair. Ford, using technology bought from West Germany's Audi-NSU-Wankel, is also extensively testing the Wankel. Chrysler officials are the least enthusiastic about a rotary revolution. Engineering Vice President Alan Loofbourrow recently predicted that the Wankel "will turn out to be one of the most unbelievable fantasies ever to hit the world auto industry." Few other auto executives would go nearly that far; almost all insist that they must still cross several important bridges--especially the higher fuel consumption problem--before putting a rotary engine into mass production.

Even so, David Cole and other researchers are convinced that they are on the way toward ironing out the remaining problems with the Wankel. Rotary engines now available, including the Mazda, says Cole, are "equivalent to a 1930s' piston engine in development. The comparison between that and what we will see in a couple of years will be quite impressive." The Wankel seems finally to be doing what automen long thought impossible: ending Detroit's long love affair with the standard engine, or at least making an interesting triangle out of it.

* Last week Assistant Interior Secretary Hollis M. Dole predicted that ordinary auto gasoline may become "in tight supply in certain sections of the country by late summer of this year."

This file is automatically generated by a robot program, so reader's discretion is required.