1970 Chevrolet Chevelle Malibu entered by the Tufts University team in the 1970 Clean Air Car Race. Photo from the Tufts Digital Library.

The whine of a turbine filled the air. Electric cars scooted around without making a sound. Steam cars chuffed their way to the starting line. Propane, natural gas and other exotically fueled cars waited in the wings. And among the 50 or so experimental and prototype vehicles that participated in the cross-country 1970 Clean Air Car Race, the technology from a handful of them would go on to help make modern cars cleaner.

In 1970, the pall of protests hung in the air at college campuses across America. Restive students agitated for social, political, and environmental change, and the protests had started to take a violent and deadly turn. Also in 1970, a literal pall of smog hung in the air at many of those same college campuses. While smog plagued some areas of the country as far back as the Teens, and efforts to clean up stationary polluters began in the early 1950s, the identification and cleanup of mobile polluters didn’t begin in earnest until the early 1960s in California, later in the decade across the rest of the country.

Just as the overall environmental movement led to the creation of the Environmental Protection Agency and the celebration of Earth Day that year, the increased attention on tailpipe emissions led to the 1970 Clean Air Act – popularly known as the “Muskie Act” after Senator Edmund Muskie’s role in drafting the bill – which updated similar, but less far-reaching, Clean Air acts of 1955, 1963 and 1967. Under the Muskie Act, for the first time the country’s automakers had to implement controls to reduce certain tailpipe emissions, including carbon monoxide, hydrocarbons and nitrogen oxides by up to 90 percent – and they had to do so within five years. “If they can gear up for a war, they can gear up for public health,” Muskie said at the time.

Even before the Muskie Act became law, Detroit’s automakers voiced their opposition, claiming they couldn’t meet such stringent standards in so little time. But another narrative ran counter to Detroit’s opposition, pointing out that the technology to meet and surpass the standards in the Muskie Act not only existed, but could be implemented in a roadworthy automobile.

Among those making the counter-argument were environmentally minded college professors and students, in particular those in the engineering departments at the Massachusetts Institute of Technology in Cambridge and at the California Institute of Technology in Pasadena. In 1968, a CalTech engineering student, Wally Rippel, issued a challenge to MIT students: Build an electric car and make it to our campus before we can make it to yours in our electric car.

Breakdowns and other mishaps befell the so-called Great Electric Car Race, but both entrants finished the race (CalTech won, thanks to penalties levied against MIT), and the experience showed that the potential at least existed for cars to make such a cross-country run while emitting drastically less pollutants than those coming off of Detroit’s assembly lines.

So in October 1969, folks from MIT and CalTech got together to reiterate their challenge. The next race would take place in August 1970. It would run from Cambridge to Pasadena, and this time, they would open up the race to any college that wanted to participate. They’d also allow more than just electric cars to compete in this race: Initially, the rules called for three classes – one each for electric, steam, and turbine power – but as word spread and as various university engineering departments began to respond to the race requirements, the rules committee added a few classes for vehicles with internal combustion engines: one for liquid-fueled engines, one for gaseous-fueled engines and one for hybrids.

The rules for the race were actually rather simple: Vehicles had to have four wheels, they had to carry at least two average-sized adults, they had to maintain a minimum speed of 45 MPH over level ground, and most important of all, they had to meet the upcoming 1975 federal emission standards.

The judging, however, ended up a Byzantine affair that would later prove contentious. Vehicles were scored not only on whether they completed the race (which was more of a rally, with scheduled stops in Toronto; Detroit; Champaign, Illinois; Oklahoma City; Odessa, Texas; and Tucson), but also on how they performed across a variety of categories (including noise, handling and acceleration) and on how little they polluted along the way, with tailpipe measurements taken in Cambridge, in Detroit and again in Pasadena (according to MIT, powerplant emissions were factored in for the electric vehicles). “Class winners were determined by a mathematical formula which proved in some instances to be as whimsical and arbitrary as the judging panel,” Jim Henry wrote in the September 24, 1970, edition of The California Tech, CalTech’s student newspaper. The crowning of an overall winner would prove even more opaque and generate quite a bit of controversy.

The University of Wisconsin’s two entries: A Lotus Europa running unleaded gas, and an Opel GT running propane.

The response was enormous. At least 32 colleges and four high schools submitted more than 40 entries in all six classes. That’s likely due to a few factors: First, race organizers allowed participants to solicit and receive assistance from corporations; though not every team took advantage of the fact, many at least used it to secure sponsorships and funding for their projects. Second, General Motors stepped in to provide a number of Chevrolet Chevelle sedans for use as entries or as support vehicles (Saab, too, supplied a car to Worcester Polytechnic), and the National Air Pollution Control Administration pledged to lease each category winner after the race to study it, essentially a prize of $5,000.

Along the way, students participating in the design, build and competition for the race would present reams of papers on their experiences and findings and would earn countless credit hours.

Opening the race up to corporations, some argued, led to a number of companies essentially entering the race themselves behind student fronts. The move also led to some unexpected developments. For instance, Louisiana State University’s entry, a 1970 Pontiac Le Mans four-door sedan, used a 400-cu.in. Pontiac V-8 and fueled up on regular leaded gasoline; aside from some thermal reactors and a particulate trap in the exhaust system, about the only modification made to it was a special carburetor developed by the Ethyl Corporation – the entity behind the promotion, manufacture and distribution of leaded gasoline.

On the other end of the spectrum, some of the entries showed extensive student-led innovation and experimentation. MIT’s 1970 Chevrolet C-10 pickup used a jet turbine mounted under a camper shell – with an exhaust stack exiting where the tailgate normally resided and angled to point straight up – to spin a generator that charged a bank of batteries that in turn powered a 600-hp DC motor. At least a few schools entered vehicles fabricated from the ground up, as did the University of Toronto with its Miss Purity, which mounted a student-designed fiberglass gullwing body on a custom chassis and then powered it with a propane-converted 302-cu.in. Chevrolet V-8 that ran a parallel hybrid drive system.

By far, though, the most popular class was the gaseous fuel class, with 20 entrants, 13 of which converted their regular gas cars to run on propane (and one of which – the entry from Putnam City High School in Oklahoma City, developed for the school by Corken International – converted its Opel GT to run on either propane or compressed natural gas).

And that’s just the official entry list. The months leading up to the race produced several vehicles that didn’t make it to the starting line for one reason or another. One of the University of California San Diego’s campus police cars, part of a fleet already converted to propane, was destroyed in a one-car wreck on its way from San Diego to Cambridge. At least a couple of cars, including Boston University’s Avis-sponsored custom-built battery-electric car, appear in coverage of the race, but not in the official entry list. And a group of MIT students and staff even attempted to convert a two-stroke three-cylinder Saab to single-acting uniflow steam power.

“We had it running briefly, but after 20 minutes of running it seized up,” said David Nergaard, who designed the steam engine, but said the flaw came from an advisor’s suggestion they use steel bearings. “It also became obvious by the time the race was approaching that our steam generator wouldn’t be ready, and besides, it wouldn’t fit under the Saab’s hood.” So in response, he said he rolled his Stanley steam car across the starting line. “The Ford people running the emission tests in Cambridge weren’t happy that a 50-year-old piece of technology was as advanced as some of their modern cars.”

The UCSD steam-powered AMC Javelin. Photo from Ray Salemme.

Of the two steam-powered cars that started the race – UCSD’s AMC Javelin and Worcester Polytechnic Institute’s Chevelle – neither finished, and thus the category went without a winner for the race. The Javelin, however, deserves a special mention, if not for its already-in-development powerplant – a 74-cu.in. Harley-Davidson V-twin with custom rotary valves designed to run under 800 pounds of steam pressure and produce about 75 horsepower – then for one of its designers, a UCSD chemistry professor named Stanley Miller, who nearly 20 years earlier had conducted a famous series of experiments related to the origin of life.

Some of the original competitors from the 1968 race showed up as well: MIT’s Corvair switched from a battery-electric drivetrain to a serial hybrid drivetrain for the race, while Rippel, the instigator of the 1968 race, helped Cornell design and build its all-electric 1970 AMC Hornet. CalTech, for its part, decided to enter two cars converted to compressed natural gas – another 1970 AMC Hornet and a 1970 Ford Ranchero – largely because an electric car would have consumed too much development time.

LIFE magazine photo of some of the entrants in the 1970 Clean Air Car Race on the morning it left from Cambridge.

Disputes about race rules began even before the official August 24 start of the race. Even though the emissions results counted for roughly twice the performance testing in the final tally, some of the teams with steam-, electric- and turbine-powered vehicles complained that the internal combustion-powered entrants had begun to treat the event as an actual race to the finish; the electrics got a two-hour head start in response (probably explaining why none are in the group shot that appeared in LIFE magazine, above).

Finally getting a good look at the other cars in the race, the teams primarily run by students registered their displeasure at the extent of corporate involvement among their competitors.

And quirks of the rulebook and emissions testing procedures befuddled some teams: For instance, the CalTech Hornet scored highest on the emissions testing in Cambridge, but an exhaust leak midway through the race forced it into last place not necessarily because it ran dirtier than other entrants, but because of the wide differential in emissions output between the start and end of the race.

Still, the race generated plenty of publicity. The Today Show included an interview with participants before the race, and several accounts of the pre-race preparations note that the student teams had to not only get their vehicles running right, but also conduct interviews with reporters at the same time. Popular Science and Popular Mechanics wrote up the race, both before and after the event.

Even as the war in Vietnam continued and the trial of the Manson family for the Sharon Tate murders took place, the race grabbed front-page headlines as it made its way across the country, and the CBS Evening News followed the race’s progress every night. Reporters noted which teams led the race at various stages and wrote about the exhaustion of the drivers and mechanical maladies the teams suffered toward the end of the race.

Through it all, cameras rolled, filming the event for an Orson Welles-narrated documentary. And the towns that hosted the race made the best of it: Champaign officials presented the keys to the city to the students; Oklahoma City businessmen treated the students to a buffalo steak barbecue.

Some cars didn’t make it the entire way across the country. WPI’s steam-powered Chevelle, the Great Teakettle, dropped out, as did the UCSD steam-powered Javelin, which made it about a half-mile beyond the starting line, unable to meet the minimum speed for the Massachusetts Turnpike. The four battery-powered electrics, which benefited from a network of charging stations set up along the route by local utilities, fared a little better: Georgia Tech’s Volkswagen-based Elect-Reck made it to the Mississippi River, and even then only with the prodding of race organizers, while the Cornell AMC Hornet at least made it to the finish line.

Others, meanwhile, became minor stars along the way. Just about every account of the race mentions at least two entrants: the University of Toronto gullwing, and the MIT turbine-powered C-10, which burned leaves off of trees all along the route and reportedly shredded the banner that hung over the finish line on the CalTech campus. Science fiction author David Brin, at the time an undergrad at CalTech and a member of the Clean Air Car Race coordinating committee, recalls the truck giving “ear-splitting demos to the press” while parked just outside his dorm room. Both took class wins, though the pickup did so only by dint of having the turbine class all to itself, and the University of Toronto gullwing shared its class win with WPI’s Gremlin.

Other class winners included the Cornell AMC Hornet for the electric car class, WPI’s propane-powered 1970 Chevrolet Chevy II Nova four-door sedan in the gaseous fuel internal combustion class, and Stanford’s methyl alcohol-powered 1970 AMC Gremlin in the liquid fuel internal combustion class.

The Caprang, a 302-powered Mercury Capri running unleaded. Photo courtesy Wayne State University.

The overall win, meanwhile, went to Wayne State University’s Caprang, a 1971 Mercury Capri fitted with a 302-cu-in. V-8 from a Ford Mustang, a C-4 automatic transmission, and a 2.33 rear. The team – which consisted of captain Richard A. Jeryan, Brian Geraghty, Mike Riley, John Karol, Alden Raquepau, Lawrence P. Wagle and Dan Harmon – fitted a fiberglass hood, doors and decklid, along with plexiglass side and rear windows for weight reduction.

And rather than convert to propane or natural gas or hybrid drive, they installed a low-overlap camshaft to reduce nitrogen oxide emissions, added off-the-shelf catalytic converters and an EGR system, and isolated the carburetor from the rest of the engine compartment to precisely control its temperature. They didn’t run straight gasoline from the pump, however. Instead, they ran the engine on lead-sterile gas.

The selection of the Caprang as the overall winner didn’t sit well with many of the other participants. It didn’t win its class, after all, and one account of the race claims that it failed to meet the 1975 emission standards that race organizers made central to the competition (a claim that probably resulted from the car’s emissions test in Detroit, when a manual choke accidentally left open caused the car to register high carbon monoxide readings; the Caprang’s subsequent emissions test in Pasadena reportedly resulted in readings that almost surpassed the 1980 emissions standards).

Moreover, the Wayne State University team, as it turned out, was allegedly made up of carburetor engineers then employed by Ford and taking night classes at the school; the team initially couldn’t collect their winnings because Ford Motor Company held at least partial ownership of the Caprang.

“(The Clean Air Car Race) turned into an advertisement for a patched-up gas model which allows the major automotive companies to look like they’re doing something and they’re not,” said Peter Lord, a member of the Cornell electric-car team.

But, if nothing else, the Caprang’s win did show a way forward for Detroit’s automakers. If General Motors, Ford and Chrysler couldn’t – or wouldn’t – dedicate the resources to develop more exotic steam, turbine, or electric powerplants (Nergaard maintains GM deliberately killed its steam and turbine programs by intermingling the teams working on those programs), they could at least meet federally mandated emissions regulations by using an assortment of proven emissions control devices – catalytic converters, EGR valves, air injection systems, capacitive discharge ignition systems and careful tuning – combined with a switch from leaded to unleaded gasoline.

“I think the race markedly helped our cause and stirred some emotional interest in the program,” said John Brogan of the Air Pollution Control Administration.

Some were more direct in their evaluation of the results.

“We’re trying to show the industry that the technology exists to reduce pollution,” said Alan Goldberg, then a 21-year-old MIT student. “If students can do it and make their cars go across country, the industry can do it.”

Indeed, within five years of the race, all of the above emissions control devices became commonplace under the hoods of American cars. The phaseout of leaded gasoline took a little longer, starting in 1973 and lasting through the mid-1990s, while fuel injection wouldn’t make it to American cars until the early to mid-1980s, and hybrids wouldn’t begin to appear until the early 2000s.

Even so, those latter developments were years, if not decades, in the making, and many argue that the automakers in America and around the world began their research into fuel injection, hybrids and viable electrics as a direct outgrowth of the environmental movement of the late 1960s and early 1970s. Take, for instance, the first-ever Symposium on Low Pollution Power Systems Development, which took place in 1973 with widespread participation from Detroit’s automakers.

“It turns out that the most historically significant thing we accomplished was effected by the least romantic or innovative vehicles in the race,” Brin wrote. “Those boring old internal combustion cars that made it across the country on unleaded gas without any explosions. Not even any excess engine wear. They still went vroom in Pasadena, and then were driven all the way back east again and the public noticed. Poll numbers shifted. Within 18 months the EPA had enough support to start acting to reduce lead poisoning.”

For all of its positive impact, the 1970 Clean Air Car Race would end up the only such Clean Air Car Race. It proved costly, even with corporate and industrial support: MIT’s final tally of the expenses for the race amounted to $265,490, or about $2 million in today’s dollars, most of that amount going to the film contract for the documentary.

A follow-up race of sorts, the Urban Vehicle Design Competition, took place in 1972, with less of a focus on cross-country travel and more on a car’s suitability to an urban environment. While it lacked the glamor and adventure of the 1970 Clean Air Car Race, the Urban Vehicle Design Competition still managed to attract dozens of entrants from across the country with an equal variety of experimental engines running exotic fuels.

How many of the vehicles from the 1970 Clean Air Car Race still exist is uncertain. We’ve only found evidence of two: An electric Honda motorcycle, an unofficial entry from Campolindo High School in California; and the WPI Gremlin that shared top honors for the hybrid class. The latter now sports a 650-hp AMC V-8 and conventional drivetrain capable of pushing the Gremlin into the 11s in the quarter mile.

Even so, that Gremlin’s owner doesn’t have to turn its headlamps on in the daytime to plow through heavy smog.

The official entry list for the 1970 Clean Air Car Race: