Toyota’s history in international sports car racing is coloured with the trials and successes of some of the most iconic prototypes that have ever raced. The 24 Hours of Le Mans-winning TS050 Hybrid and the GR010 Hybrid hypercar are just the latest in a lineage that is commonly traced back to the Dome “C-V” prototypes of the ’80s and early ’90s. They were succeeded by ’90s icons such as the V10-powered TS010, the impervious Eagle Mk.III built by All American Racers, and the grand touring prototype TS020, better known as the “GT-One.” Succeeding these cars were the TS030 and TS040 Hybrid LMP1s, which laid a successful foundation in the early 2010s for the TS050 and GR010 to follow.
It is only fitting that this installment of Sportscars That Never Raced will be published in the afterglow of the GR010’s first victory at Le Mans, won by the trio of Mike Conway, Kamui Kobayashi, and José Maria López. In victory, a Toyota carrying the number seven has won the greatest prize in endurance racing. And for avid scholars of Toyota’s racing history, a Toyota with the number seven will likely evoke strong emotions and vivid memories of the Japanese manufacturer’s first foray into prototype sports car racing from half a century ago: The infamous “Toyota 7” project of 1968-1970.
To be certain, the “Toyota 7” name was bestowed to three very distinct vehicles that represented a clear stage of the project’s evolution. But for many who know of the legend of the Toyota 7, the name is most synonymous with its final evolution from 1970. A groundbreaking race car that was years ahead of its time, one whose legacy endures as an emblematic machine of its era despite the fact that it never raced.
It is the 578A, the internal codename for the car better known as the Toyota 7 Turbo.
The Toyota 7 was a joint-developed project between Toyota Motor Corporation and Yamaha Motor Company. Its roots trace back to Toyota and Yamaha’s first collaboration, developing the groundbreaking Toyota 2000GT sports car under the supervision of project leader Jiro Kono (河野二郎). Kono was the manager of motorsports activities for Toyota from 1964, and in 1966, he established Team Toyota – the first, and only, factory racing programme solely operated by the Japanese arm of Toyota Motor Corporation.
Not long after the 2000GT entered production in the autumn of 1966, Kono would again coordinate a joint-development project between Toyota and Yamaha in the spring of 1967, to construct a new vehicle built to the FIA Group 7 two-seater sports car regulations that were about to transform the annual Japan Grand Prix Car Race at Fuji Speedway. Nearly a year’s worth of research and development would manifest into the first generation Toyota 7, the three-litre 415S, which made its debut in the 1968 Japan Grand Prix.
From 1968 to 1969, Toyota and Yamaha would use the lessons learned from the 415S to develop its successor, the five-litre 474S, popularly known as the “New Toyota 7”. It originally made its debut as a closed-cockpit coupé, before eventually transforming into an open-top roadster with its distinctive silhouette. By this time, Daihatsu Motor Company – a subsidiary of Toyota, who had modest success in racing on their own – had joined the project. The new shape of the 474S was crafted from hours of testing in Daihatsu’s wind tunnel, which became an integral facility.
Toyota were the largest Japanese auto manufacturer in the 1960s, and their success in the automotive world meant that their racing programmes were always well-funded. Kono and his top consultant Eizo Ikeda (池田英三) scouted and recruited a slew of talented drivers to race for Team Toyota, led by captain Shihomi Hosoya (細谷四方洋), a selfless, gracious competitor whose innate driving skill and engineering background made him the perfect candidate to be the lead development driver of the 2000GT. Toyota dominated the early years of Japanese endurance racing, highlighted by overall wins in the Fuji 24 Hours, Fuji 1000km, and Suzuka 1000km races – plus the successful 2000GT Speed Trial at Yatabe.
But in the 1960s, the Japan Grand Prix was the biggest race in the nation by an order of magnitude, equal to the Indianapolis 500 and Monaco Grand Prix in the eyes of the nascent Japanese racing world. It was the race for which the Toyota 7 was developed above all others. And it was the stage where Team Toyota always fell short of victory, overshadowed by their arch rivals. Nissan’s R381 and R382 prototypes drove into the history books with victories in 1968 and 1969, upstaging each of the first two generations of Toyota 7 on the road to glory.
Behind the Japan Grand Prix, the biggest sports car race in Japan at the time was the annual World Challenge Fuji 200 Mile Race, also referred to as the “Japan Can-Am.” It was an all-star invitational event held in November 1968 and 1969, where top drivers from the Canadian-American Challenge Cup would compete against the best that Japan had to offer. Toyota accepted the challenge each of these years. While Toyota couldn’t compete for the top honours in ’68 with their underpowered 415S, an upgraded version of the 474S was vastly more competitive the following year.
In a significant upset against several Can-Am regulars, 26-year-old Minoru Kawai (川合稔) won the 1969 Fuji 200 Mile Race aboard his white and blue Toyota 474S. He delivered Team Toyota a signature win. A declaration that they had the machines, the engineers, and the drivers to compete against the best that Japan – and the rest of the world – had to offer.
Kono-san, the boss at Team Toyota, always had grand visions for his team beyond competing in Japan. From his first year on the job, he expressed a desire to compete in Formula One against the likes of Honda. The beautiful 2000GT was originally conceived to race at Le Mans. While neither of these plans materialized, the prospect of competing in America with a factory Toyota was irresistible for Kono. Not long after Kawai took the chequered flag in the Japan Can-Am race, Jiro Kono had told Motor Sport Magazine that his team was preparing to compete in the Can-Am Series in 1970.
To realize the dream of a long-awaited victory in the following year’s Japan Grand Prix, and to challenge the very best of the Can-Am Series on a regular basis, a third generation of the Toyota 7 would be developed by the triad of Toyota, Yamaha, and Daihatsu. It would need to be a car that could not only fend off the challenge of Nissan’s R382 successor at home, but also the likes of the dominant factory McLarens from abroad. This, is where the magnificent Toyota 578A, the “Turbo 7”, enters the story for the first time.
Most of the legends and tall tales about the Toyota 578A are legends of the powerplant that was bolted to the back of all but one example of this elegant two-seater, the 91E. The 91E was based on Toyota’s previous 79E: A five-litre, double overhead cam, 32-valve V8 engine based upon Ford and Cosworth’s revolutionary DFV. The 79E was a powerful engine in its own right, producing 530 horsepower at 7600 RPM, and 520 N∙m of torque at 5600 RPM. The Japan Can-Am spec brought the power up to 590 HP @ 8400 RPM.
But the 91E was a different beast entirely. While Bobby Unser’s victory in the 1968 Indianapolis 500 aboard an Offenhauser turbo-V8/Eagle demonstrated some of the potential for turbocharging in auto racing, it hadn’t been seriously explored as an option in sports car racing – not even in the “anything goes” world of Can-Am. That was about to change with the introduction of Toyota’s newest racing engine.
The idea came from Shunji Tanaka (田中俊二), the manager of Yamaha’s automotive research division. While living in Europe, Tanaka met with former racing driver turned engineer, Michael May. It was in this meeting that May tipped Tanaka towards the potential that a turbocharged engine had to offer. This is where it would be fitting to move forward by saying that ‘the rest was history,’ except that during testing, the engineers at Toyota and Yamaha were blowing through turbines at an alarming rate. The Garrett AiResearch turbochargers they had contracted to use were originally meant for use in diesel engines, and the turbine fans couldn’t cope with the strain of a high-strung petrol engine.
At the behest of Yamaha’s president, Genichi Kawakami, (川上源一), senior managing director Hironori Ogura (小椋宏典) flew to America to try and find a solution for their troublesome turbine fans. Ogura found it in the alloy Iconel, which was capable of withstanding the heat of 1,000°C for over 100 hours. It was a breakthrough for the engineers at Yamaha in their search for reliability.
Visually, the 91E was distinguished from its predecessor by way of the rounded cylinders that sat atop the velocity stacks, as well as the two Garrett turbines, prominently featured at the rear of the car (in period, they were even painted to match the colour of the body for additional visual flair).
Toyota officially rated the 91E at 788 HP @ 8000 RPM – sometimes rounded up to an even 800 HP – with 725 N∙m torque @ 7600 RPM. But ask anyone involved in the Turbo 7’s development and they’ll tell you that “a modest understatement” barely begins to describe the difference between the published numbers, and the actual power this engine was meant to produce. “The turbo version [of the Toyota 7] was extremely powerful for its time. It was nominally rated at 800 hp, but it was more than that,” remarked Hosoya in a 2012 talk show appearance. In a subsequent interview with Racing On magazine from May 2013, Hosoya added to his claim: “In fact, it would have produced 1,000 horsepower.”
Just to put that into perspective: The Bolthoff-tuned Chevrolet V8 engine in the 1970 Can-Am championship winning McLaren M8D was making “only” 670 HP at the time, while the naturally-aspirated Nissan GRX-3 V12 engine was capable of producing anywhere from 630-700 HP.
All of that power was sent to the rear wheels through a brand new five-speed transmission and triple-plate clutch, developed exclusively for the Turbo 7 by Japanese company Aisin. This contributed towards an auxiliary goal for Toyota, who were keen to build a world-class sports car that was built with as many Japanese parts as possible. Then that power was ground into the pavement through Firestone Indy tyres.
When the first chassis and engine was completed, the Toyota 578A was – with absolutely no exaggeration – the most powerful racing vehicle ever built.
But it is worth noting that one example of the 578A was fitted with the naturally aspirated 79E powerplant, in its late 1969 specification. This N/A version of the Turbo 7 was driven in a demonstration run at Fuji Speedway by Hiroyuki Kukidome (久木留博之), a talented young driver that came over to Toyota by way of the Daihatsu partnership.
It’s easy to get lost in the mouth-watering horsepower numbers that draw the most attention to the Toyota 578A. But what often goes overlooked is how much work Toyota and Yamaha put into transforming the chassis and body, to make the car lighter, and more friendly to drive. Well, at least as friendly as a Can-Am car from 1970 producing over one horsepower per kilogramme could be, anyway.
Finding the right chassis for the Toyota 7 was a case of trial and error for Toyota and Yamaha. The 415S’ aluminium monocoque suffered from rigidity issues during testing, which led to the car having to take on additional weight to fix the issue. The 474S saw a switch to a steel pipe space frame construction similar to the Nissan R381, but was still not as rigid or as light as the engineers had hoped. Toyota purchased a McLaren M12 chassis, and ran it in the 1969 Japan Can-Am race, for development purposes as they sought out to identify and eliminate the weaknesses of their own design.
The process of transforming the 578A into a more potent racing vehicle began with the construction of a new space frame chassis constructed of aluminium alloy, which proved to be more rigid than the old steel space frame. This was part of a number of weight-saving techniques done to shed roughly 100kg to offset the heavier turbo powerplant. The Aisin SR-55’s gearbox case was made of magnesium alloy, the suspension arms were made of titanium – whatever parts could be replaced with lighter titanium or magnesium alloys, it was done, to reduce the dry weight to a svelte 620 kilogrammes. And one more note about the engine: it was now bolted to the rear of the cockpit as a stress bearing member in the 578A, resulting in a chassis that was twice as rigid as the 474S.
The wheelbase was lengthened by five centimetres, making the car more stable through corners. Improved suspension geometry, with longer front and rear suspension arms, further enhanced the car’s handling characteristics. Underneath the body, the dual radiators from the 474S were replaced with a single radiator in front of the left rear wheel, while the right-side radiator was replaced with an oil cooler.
The silhouette of the 578A was virtually identical to the 474S, including the massive rear spoiler that was introduced for the ’69 Japan Can-Am race. But the body was brand new, constructed out of a thinner, lighter carbon-fibre reinforced plastic material that was only a millimetre thick throughout the removable front cowl. Air flowed into the radiator and oil cooler through two giant NACA duct intakes on either side of the car.
To improve aerodynamic stability, the nose of the car was squared off, with two box-shaped intakes in front of the front wheels. To reduce drag, the rear-view mirrors were now embedded within the bodywork, behind the front wheels. In total, the car was 16 centimetres wider than its predecessor.
Development of the 578A began in January 1970, and construction of the first vehicle was completed four months later in May, at an estimated cost of over ¥200 million JPY, or ~£233,121 GBP, per unit. When adjusted for inflation, the cost was over ¥666 million JPY/£4.4 million GBP per unit.
Can-Am cars of this day and age were never built to be subtle, but the Turbo 7 was a particularly blunt instrument of ferocious power. During testing, the 578A clocked a reported top speed of 363 kilometres per hour (225 mph), while it burned through its entire 250 litre fuel tank at a rate of 800 metres per litre. When Hosoya tested the car at Yamaha Fukuroi Proving Grounds in June, he smashed the lap record by over four seconds.
“There was so much torque that even in fifth gear I could spin the wheels, so I could manoeuvre the car as much as I wanted as long as I used the steering to trigger a change of direction,” Hosoya told Car Graphic writer Kazuo Higaki during a series of interviews published in 2003. “The turbo lag could be compensated for, by using techniques such as pressing the throttle earlier.”
It’s also worth noting that this car – which again, was capable of producing well over 1000 HP per tonne – was smaller in stature than the current Toyota GR Yaris hot hatch.
“I’ve driven more cars than I can count, but that turbo car was definitely the best,” Hosoya concluded.
Certainly, the 578A had the potential to excel in competition on both sides of the Pacific. It was the culmination of years of dedicated work by the brightest engineers and mechanics of three different companies. The end result was a car that had solved all of the problems of its predecessors, and was more powerful than anything that had come before it. While Nissan were hard at work building the new R383, in the months leading up to the 1970 Japan Grand Prix at Fuji Speedway, Toyota were now being talked up as the prohibitive favourite to finally defeat their greatest domestic rivals and win the one big race that had eluded them for years.
That dream of a long awaited Japan Grand Prix victory was destroyed on the morning of 12 June, 1970. Four days after Nissan pulled out of the event citing environmental concerns, the Japan Automobile Federation made the difficult decision to cancel the Grand Prix – bringing with it the end of Japan’s brief, yet memorable love affair with the Can-Am styled “Big Machines”.
Team Toyota, however, continued to press on with the development of their “Turbo 7” – now squarely aimed at a Can-Am challenge overseas. On 26 July 1970, three 578As took to Fuji Speedway for a public demonstration run prior to the annual Fuji 1000km race. Hosoya and Kawai each drove a turbocharged version of the 578A, while Kukidome drove the lone N/A version. The crowd was captivated by the awesome sound of the turbo V8 engines. Surely, they must have imagined that a Japanese car and a Japanese driver could win the Can-Am championship, sooner rather than later.
All the while, a changing of the guard had finally taken place at Team Toyota in regards to their driver lineup. Hosoya was still a very capable driver, but he was also willing to sacrifice his own success for the benefit of his younger teammates. By 1970, he was ready to let one of his younger teammates succeed him as the captain of the team, but all of them, save for one, were gone. Yoshio Otsubo (大坪善男), Hosoya’s long-time endurance racing co-driver, retired after a succession of injuries and an acrimonious split with Toyota. Hiroshi Fushida (鮒子田寛) may have been the best all-around talent that Team Toyota ever had in the ’60s, but in 1970, he left Toyota – and Japan – to try his luck racing in America, as a freelancer.
But the most painful loss that Toyota endured was the death of Sachio Fukuzawa (福澤幸雄), one of the most popular and naturally gifted drivers to emerge from the early years of Japanese motorsport, in a testing accident at Fukuroi on 12 February, 1969.
Minoru Kawai’s triumph in the 1969 Japan Can-Am race, however, immediately marked him as Toyota’s ace of the future. He was talented, and he had commercial appeal for the company – becoming the face of Toyota’s ad campaigns alongside his wife, the actress and former race queen Rosa Ogawa.
And by July 1970, Toyota now saw Kawai as the ace of the present. He was ready to come to America as Team Toyota’s new captain and lead driver of the next decade. All that remained was for the board of directors at Toyota, led by president Eiji Toyoda (豊田英二), to sign off on this new racing challenge. That confirmation came on the morning of Wednesday, 26 August 1970, when Toyota’s board of directors approved the plans to go racing in America.
That afternoon, a private test was being carried out at Suzuka Circuit with Hosoya and Kawai taking part. That day, Kawai reportedly set a new course record in the Turbo 7. Towards the end of the session, Hosoya watched from the pits as Kawai’s car roared down the frontrstretch, the sound of his turbo V8 engine echoing throughout the fields for one final lap.
But as Kawai drove out of Degner Curve and underneath the crossover bridge, his Toyota suddenly lost control, leaving skidmarks as it left the course. It is believed that the throttle stuck open, and Kawai had slammed on the brakes before his car hit a trackside ditch at 200 kilometres per hour, ejecting him from the cockpit upon impact.
He was immediately rushed to the hospital, but just thirty minutes later, Minoru Kawai was pronounced dead at the age of 27. A day that was meant to ring in the start of a new chapter for Team Toyota, had now become an evening of sorrow.
Kawai’s fatal accident at the wheel of the 578A came 18 months after Fukuzawa died while testing an unidentified prototype based on the Toyota 7 project. These deaths were each tragic in their own right. But what compounded the grief of Kawai’s death was the fallout from Fukuzawa’s accident, where Toyota were accused of tampering with the investigation in order to protect confidential trade secrets. Soon, the Fukuzawa family would take legal action against Toyota. With that grim spectre lingering over Toyota, a second testing fatality – and the added negative publicity that would have accompanied it – became too much for them to bear.
The following day, Team Toyota suspended its racing activities indefinitely. Their next move was inevitable, but by September, Toyota made it official: They had ceased all development on the 578A, bringing with it the end of the Toyota 7 project. By the end of 1970, the decision was made to fold Team Toyota, in favour of a new racing structure built around factory supported club and privateer outfits headed by the Toyota Motorsports Club (TMSC-R).
Just like the Nissan R383, the Toyota 578A sat in storage for the next three decades, while a new generation of Toyota prototype sports cars began to take to the circuit throughout the ’80s and ’90s.
But as Toyota were preparing to enter Formula One at the turn of the century, a restoration committee supervised by the great captain Hosoya and Toyota executive vice-president Akihiko Saito, and carried out by volunteering employees, helped bring the lost 578A back to life again. The project started with restoring the N/A version of the 578A, which first appeared at the 2002 Goodwood Festival of Speed and then the Toyota Motor Sports Festival at Fuji.
The following year, the turbocharged version was restored, and it also had the chance to run at Goodwood and the TMSF at Suzuka Circuit.
Every living member of Team Toyota’s past was reunited for the demonstrations in Japan, while at Goodwood, Toyota F1 drivers such as Allan McNish and Cristiano da Matta had the chance to drive the N/A and turbo versions of the 578A up the hill.
Both versions of the 578A, along with the last 474S, still regularly appear at what is now known as the Toyota Gazoo Racing Festival. In addition, the “Turbo 7” was also immortalized in the best-selling video game Gran Turismo 4, and has also been replicated as a Tomica diecast model on a number of occasions. These efforts have ensured the enduring spirit of the Toyota 7’s legacy, along with the two other surviving examples – one of which is on display at the Toyota Automobile Museum in Nagakute, and the other at the Louwman Museum in the Netherlands.
When assessing the legacy of the Toyota 7, it is impossible to look past the deaths of Kawai and Fukuzawa which, fairly or not, have stained its reputation in the eyes of a few well-studied fans. In hindsight, it may have been the origin of Toyota’s frustrating Le Mans “curse” that lasted for decades, but the deaths of two beloved and respected racing drivers should never be reduced into mere fodder for sporting superstition (which has now been vanquished, in any case).
As a racing vehicle, the final Toyota 7, the 578A, is a misunderstood landmark in the history of motorsport. It was built more than a year before the Porsche 917/10 made history as the first turbocharged sports car to compete in Can-Am. It was the genesis of every groundbreaking Toyota sports prototype to follow.
And, in an era of excess speed, the Toyota 578A – despite it never racing in period – stands out as perhaps the single vehicle most synonymous with its time and setting. And there is no other unraced car of any other period, before or since, that can legitimately make that same claim to fame.
Information Sources: Racing On Magazine Vol. 464, 15 May 2013; Car Graphic Magazine Vol. 507/509/511, June/August/October 2003; Hirofumi Makino’s indispensable “The Legend of Automobile’s Village” web page
Images courtesy of: Fuji Speedway, Toyota Automobile Museum, Toyota Motor Corporation, Wikimedia Commons, and Mr. Makoto Katou
