In round 4 of the F1 world championship in 1976, Tyrell introduced a revolutionary concept under the name of "P34" (Project 34). The whole concept meant the introduction of a six-wheeler f1 car for the first time ever in grand prix history. Other teams also tried the concept of a six-wheeled car until around the early eighties, but those cars were never operational in a formula 1 grand prix. In 1976 the Tyrell P34 initially was a very successful car, even winning a grand prix in Sweden. However, near the end of 1976 and during 1977 performances started to drop off considerably and in 1978, Tyrell was back with the traditional four-wheel drive car. The loss of the six-wheeled F1 car was mainly attributed to the fact that the four small front tires lacked development. Under current F1 rules a six-wheeled f1 car is prohibited.