Gordon Murray is probably one of the best car designers in the world. In the past he designed the epic McLaren F1 supercar, still one of the best supercars ever made. He also designed race cars for the Formula 1 teams Brabham and McLaren, with the greatest potential being the 1988 McLaren MP4/4. And more recently, of course, he has his own company, Gordon Murray Automotive, which has designed and built the truly amazing T .50 and is well on its way to unveiling the T.33.
However, there is one car that may stand out, including the MP4/4. In 1978 Murray joined the Brabham team, with drivers Niki Lauda and John Watson at the wheel for that season, with Nelson Piquet joining them on the final lap. The 1978 Brabham was the BT46 and during the Swedish Grand Prix Brabham came onto the track with a modified version called the BT46B. What Murray and fellow designer David Cox had created was an extraordinary fan car, generating so much downforce that the teams forced him to ban after he competed in just one race, which he easily won. This is the story of that car.
The BT46 in standard form
The BT46 had made its racing debut at the third round of the 1978 F1 season, the South African Grand Prix. The car was powered by an Alfa Romeo Flat-12 engine that produced 520 hp, some 50 hp more than the Cosworth DFV used by most teams at the time. The BT46 was fast, even in conventional form, but the one thing that really teased the car was its reliability. Lauda drove 14 of the 16 races of the year with the car and he took the podium in every race he finished. But he only finished five and retired from the other nine events.
Watson was in a similar position, delivering consistent results and numerous podium finishes, but withdrew from five races in the car. It was around this time that the ground effect had become a factor in car development, that is, the effect of using the underside of the car to generate downward force and almost suck the car to the ground. This was plain to see for all to see, with the Lotus Type 79s using this to perfection in the 1978 season.
The Brabham in fan form
At the start of the year, Murray understood exactly how Colin Chapman and Lotus got the Lotus 79’s downforce and grip. Murray made the ‘fancar’ together with fellow Brabham designer Cox. Murray had designed a version of the BT46 with a complex series of clutches running from the engine to a large single fan at the rear of the car. The faster the motor ran, the stronger the suction effect. Cox, meanwhile, had designed the overall layout of the car, and he and Murray could argue that the primary purpose of the fan was to cool the car, meaning the car was technically compliant. The whole car was basically sealed to the ground, the whole car was sucked to the ground producing staggering numbers of downforce.
The car was secretly tested ahead of the Swedish Grand Prix and certainly had the desired effect. Lauda described the car as unpleasant to drive and said it would stick to the road as it would on rails, but expose the driver to very high lateral loads, and if the ground effect developed at this rate, the drivers would be exhausted. at the end of a Grand Prix. Despite this, the two BT46Bs went to Anderstorp for the Swedish race. Watson and Lauda deliberately put the cars second and third on the grid, so as not to reveal the huge advantage of the car. The two drivers had qualified the car with full tanks to avoid pole position on the orders of team principal Bernie Ecclestone.
Lauda dominates the race
Despite protests against the legality of the car, it was allowed to race. Mario Andretti initially led in the Lotus, while Lauda jumped to second. A mistake by Andretti saw Lauda fly around him, while the Lotus would eventually retire thanks to a broken valve. Later, a backmarker dropped oil over the track, but the Brabham was unaffected. It had so much more grip on the slippery service, and Lauda wrote in his biography that as the fan was activated by the gearbox, the car only produced more grip as it got faster.
A dominant victory for the fan car
Remarkably, Lauda’s win margin of 34.6 seconds was not as great as it could have been. Lauda had again driven in such a way that he couldn’t use the car’s full potential. Watson had unfortunately dropped out of the race early on. However, the car was essentially doomed to failure. Brabham’s rivals pressured Ecclestone to withdraw the car from the series, leaving him and Murray in a dilemma, as both men knew they would easily win the title with this car. Brabham voluntarily withdrew the fan car after it won in Sweden, and while that win held, the car returned to BT46 form afterwards.
It may have been in F1’s best interest at the time that it was withdrawn, even if it is unfortunate that it was. The pace of development could have been astronomical and as Lauda predicted, drivers could collapse at the end of a race. This was also at a time when F1 was infinitely more dangerous than it was in 2022. Murray wasn’t happy about the car being retired, but this remarkable creation is arguably his greatest work. Had it been used throughout 1978, it could have become one of the most dominant cars in Formula 1 history.
Sources: Autosport, F1 Beat, RaceFans, Sports Car Digest, Wikimedia, Motorsport Magazine
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