Tyrrell P34 1976
Tamiya Tyrrell P34 1976

The Tyrrell P34 (Project 34), commonly known as the "six-wheeler", was a Formula One (F1) race car designed by Derek Gardner, Tyrrell's chief designer. The car used four specially manufactured 10-inch diameter (254 mm) wheels and tyres at the front, with two ordinary-sized wheels at the back. Along with the Brabham BT46B "fancar" developed in 1978, the six-wheeled Tyrrell was one of the most radical entries ever to succeed in F1 competition and has been called the most recognizable design in the history of world motorsports.

The P34 was introduced in September 1975 and began racing in the 1976 season. It proved successful and led other teams to begin design of six-wheeled platforms of their own. Changes to the design made for the 1977 season made it uncompetitive and the concept was abandoned for Tyrrell's 1978 season. The other six-wheeled designs ended development and F1 rules later stipulated that cars must have four wheels in total. The existing frames have since seen some success in various "classics" race events, but today are museum pieces.

The stretched versions first ran in the Spanish GP in 1976, and proved to be very competitive. Both Jody Scheckter and Patrick Depailler produced good results with the car, but while Depailler praised the car continually, Scheckter was unimpressed. The P34's golden moment came in the Swedish Grand Prix. Scheckter and Depailler finished first and second, and to date Scheckter is the only driver ever to win a race in a six-wheeled car. The car seemed to be particularly good down the straights and through long corners, like at Anderstorp, Watkins Glen, Mosport Park, Fuji and the Österreichring, but it struggled on bumpy circuits like Brands Hatch, Jarama and the Nürburgring where the grip was actually variable because depending on the contours or bumps on the track one of the front small tires would touch the road, but the one in front or behind it on the same side would not. Scheckter left the team at the end of the season, insisting that the six-wheeler was "a piece of junk".

For 1977, Scheckter was replaced by Ronnie Peterson, and the P34 was redesigned for cleaner aerodynamics, and some redesign was done on Peterson's car to accommodate his height. The P34B was wider and heavier than before, and, although Peterson was able to string some promising results from the P34B, as was Depailler, it was clear the car was not as good as before. Tyrrell blamed the problems on the increased weight, now 190 pounds (86 kg) over the 1,268 pounds (575 kg) F1 minimum. This placed more strain on the brakes and made it struggle through the corners.[3] Others have blamed Goodyear's failure to properly develop the small front tyres. Late in the season an attempt to address the handling was made by increasing the track of the front suspension, but this moved the tyres out from their original hidden position, essentially eliminating the whole advantage to the concept.

In November 1977, Tyrrell introduced his car for the 1978 season, and it had a conventional layout. He commented "In the meantime, we have closed the book on our six-wheeled project, and I am sure the cars will become something of a collector's piece". Tyrrell kept the frame that Scheckter won on, and sold the rest.

From en.wikipedia.org/wiki/Tyrrell_P34