Few engines are simpler than the humble gas turbine. Used in all manner of industrial roles, and notably the basis for the jet engines and turboprops that power modern air transportation, turbines are simple in their construction, can run on almost any combustible fuel (including gasoline, kerosene, and vegetable oils), and are relatively reliable over the long term.
Why, then, have turbines been largely overlooked when it comes to passenger cars and trucks? What prevented Detroit's Big Three from doing more than dabble with turbines in more than 50 years ago, before shunting them aside and concentrating exclusively on piston engines? It turns out that there's more to piecing together a street-ready drivetrain than just good technology—and sometimes, the future isn't as friendly as it seems in the brochure.
Technically Brilliant
On the face of things, 'a jet engine under your hood' is a phenomenal marketing campaign that seemed to encapsulate the space-race 60s, which is when turbine-powered vehicles began to make inroads among the automotive industry's engineering establishment.
There's a lot to like about these engines aside from their gee-whiz science sparkle. Composed of a pair of ultra-fast spinning turbines (one of which compresses air and then shoots it into the second turbine where it mixes with fuel and ignites), in an automotive application that rotating energy is sent to a transmission that transmits it mechanically to the wheels (as opposed to in a jet, where the exhaust gases propel everything forward).
All of the above happens to fit into a very small space, and is considerably less complex (and a lot lighter) than a piston engine, which makes it easier to place in an automotive chassis. Airflow cools the turbines (given that the rush of oxygen is a major component of its operation), and it burns cleaner than what you'd expect from a similarly-powerful combustion engine.
Valiant Efforts
The above reads like an engineer's love letter to the powertrain gods, and from the 1950s-onwards major car companies began trying to make a turbine-driven car a reality. Two major names—one on each side of the Atlantic—began to push forward with a number of turbine projects. In England it was Rover, which introduced the Jet 1 in 1949, a roadster which test at impressive speeds of up to 150-mph, and which was tweaked over the course of the next few years in a bid to bring it to showrooms. The Jet 1 program pulled directly from Rover's wartime experience in developing turbine engines for the fight against the Nazis.
In America Chrysler was the key turbine player, with its first prototype emerging in 1954. A series of publicity stunts - including driving early models across the country—would follow, but it wasn't until 1963 that the company would introduce an actual production-ready vehicle called the Chrysler Turbine, which featured a beautiful body built by Carrozzeria Ghia in Italy. For three years, the company would provide 203 drivers with a 3-month trial period behind the wheel of the Turbine as a sort of country-wide beta test of the technology. 50 examples were built in total.
For the most part, the Turbine program was a success, and during the years it was out on American roads some cars turned in a million miles of driving without any maintenance or repair issues. They also required no oil changes, and had only 20 percent of the parts as a standard gas engine vehicle.
Reality Sets In
Here's where reality sets in while discussing any practical automotive use of a turbine motor. There are a few major caveats that have prevented widespread adoption of this drivetrain, despite all of the advantages listed above.
Of these, fuel consumption is the single biggest concern. It's not unusual for a turbine engine to drink up to eight times as much fuel as a piston engine with a similar level of output. Rover discovered fairly early on that its Jet 1 car consumed gas at an indefensible rate. By adding 'regenerators' to the motor (which helped manage heat and fuel use inside the turbine), the company was able to see as much as 20-mpg out of the Jet 1's eventual successor, the T4 by 1961.
Chrysler asked its Turbine drivers to jot down as many details about the driving experience as they could, and although participants were asked to keep their impressions of the vehicle secret at the time, it's now known that roughly 14.5 miles per gallon could be expected in combined city/highway driving.
Two other major problems dogged the Chrysler Turbine. Although the vehicle produced 130hp and 140 lb-ft of torque, if driven like a normal car the coupe would feel sluggish off the line. A turbine engine needs to be brake-boosted to the 52,000 or so RPM (the vehicle idled at 22,500 rpm) where it produces peak power, and then released in a squeal of tires to accelerate quickly, as Chrysler would demonstrate again and again in racing the Turbine against some of its traditional muscle cars of the day.
Test program drivers didn't realize that, however—or perhaps they didn't want to change how they conducted their business behind the wheel - and so issues with slow starts and occasional stalling would be regularly reported.
All the driver training in the world wouldn't help Chrysler deal with the emissions issue associated with the Turbine. Although no C02 was produced by the engine, it did throw out significant levels of nitrogen oxides, which were just five years away from being slammed hard by the Clean Air Act in 1971. Chrysler had no solution for dealing with this particular pollutant, which put the Turbine program in serious trouble.
The Legacy
Rover got out of the turbine-powered passenger car business when it decided to instead focus its efforts on applying the technology to race cars. British Racing Motors would field a Rover turbine design at Le Mans for several years beginning in 1963, but the program was eventually abandoned. STP-Paxton would attempt a turbine-powered Indycar shortly thereafter, and led 171 laps of the 1967 Indy 500 until a gearing failure brought it into the pits, while Lotus would continue the charge the following year with three turbine cars at Indy and one in Formula One (before race officials extinguished future attempts via changes to the rule book).
Chrysler was facing down the triple-whammy of upcoming EPA regulations combined with confused driving impressions from its test audience and the $16,000 asking price it would have to charge to make ends meet on the project, That was three times the price of its most powerful piston cars, which also consumed less fuel and drove how the average owner expected them to.
While that confluence of factors would spell the end for the Turbine at Chrysler, the company would keep the drivetrain on the back burner for much of the next decade, producing concepts and making plans for eventual produciton. By 1979, the company was ready to put a turbine edition of its New Yorker sedan on sale within the next couple years, having figured out how to finally reduce emissions and boost mileage to acceptable levels. Despite heavy support from Lee Iacocca, chairman of the company at the time, Chrysler's pending bankruptcy and subsequent government bailout would come with a stipulation that no money be spent on the Quixotic pursuit of turbine-powered cars. It turned out to be the final body blow that would rob the world of the jet car dream.
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