Williams denies running underweight car at Jerez image

Williams has rubbished claims it set the fastest time of last week’s Jerez test by running an underweight car.

Rubens Barrichello’s best lap was comfortably faster than any of his 23 rival drivers, moving one unnamed competitor to declare he ‘didn’t believe’ he had witnessed genuine performance.

Rumours suggested the Brazilian’s new FW33 car was running low fuel, super soft tyres and an underweight car after its KERS unit was removed, mere days before 27 per cent of the Oxfordshire based team’s shares are offered on the stock market.

“Absolute nonsense,” Williams’ technical director Sam Michael told Germany’s Auto Motor und Sport. “The time is real. Anyone who knows our team knows that we don’t run underweight.

“The time is down to Rubens using the super-soft tyres, and of course he had a little less fuel in the tank.

“But the KERS elements were all on board; we only cut the connection from the generator to the engine because we had had a problem with the cooling,” the Australian insisted.

Michael said Barrichello’s time, half a second quicker than his nearest rival Michael Schumacher, could have been another few tenths quicker had the KERS been working.

As for why the FW33 was suddenly so competitive after days in the midfield, he explained: “This is because we had only used the medium tyres and always with a relatively large amount of fuel on board.

“We never got the medium tyre to work and we still don’t know why,” admitted Michael.

At the same time, Mercedes team boss Ross Brawn dismissed reports that Michael Schumacher’s second-best time at Jerez last week was a ‘glory run’ to ease pressure off the marque.

“There is little point to wasting precious track time on low-fuel ‘glory’ runs when there is far more important work to complete,” he told F1’s official website.