Flashback: The Williams F1 six-wheeler
18 March, 2011
Mar.18 (PVM) The 2011 Williams Cosworth FW33 has the smallest gearbox and the tightest rear end of any car in the 2011 pitlane, a factor that attracted many admirer’s in the Valencia pitlane where it broke cover.
But this was not the first time that the back end of a Williams Formula One car has been the focus of rivals’ attentions; in 1983 the team re-wrote the rulebook by testing a six-wheeler. Here, Director of Engineering Patrick Head reminisces about another car that got tongues wagging.
“When the flat-bottomed cars came in, engine power suddenly took on much greater significance and that favoured the turbos from Renault, Ferrari and BMW. We didn’t have a turbo in those days. We’d had a brief discussion with BMW about using theirs, but thought it too pricey so relied on the Cosworth DFV that we’d had in 1979, with less than 500 horsepower.
“We had to think of others ways in which to increase our straight-line speed and we focused on reducing the frontal area. In those days the rear wheels were enormous and caused a large proportion of our aerodynamic drag. The lift-to-drag ratio on our FW08 was about 7.5 and Frank Dernie came up with a quarter-scale model of the six-wheeler, which used four front wheels at the back, with a lift-to-drag ratio of about 12.5. So, clearly, the idea had a lot of potential.
“We produced a test car, which was a converted FW07 chassis. This first iteration of the six-wheeler was called the FW07D and it used four Goodyear front tyres at the rear. The car ran only once because we then updated an FW08 chassis to accommodate four wheels at the back and called it the FW08B.
“We were all intrigued to see if we could balance a car that had such a large contact patch at the rear and we quickly discovered that we could. I remember Jonathan Palmer telling me that he couldn’t really tell that there were four wheels at the back, although the traction out of slow corners was phenomenal.
“The FW08B had no handling problems as such – it didn’t understeer like a pig, as many people expected – but there was so much hardware on the car that it was bl**dy heavy. It was going to be a huge challenge to get it down to a reasonable weight.
“The car was about 250mm longer than a standard FW08 and all four rear wheels were driven. There was a differential between the two front wheels and the two rear wheels, but there was no diff between the front pair and the rear pair.
“In the end, the six-wheeler was banned after someone in a FOCA meeting said it would drive up costs and cause chaos during pitstops. The regulations were changed to say a car could only have four wheels, of which only two could be driven.
“After that, we had no option other than to pursue the turbo route with Honda. It was clear that horsepower was the order of the day.”