Williams chief technical officer Pat Symonds has no doubts that his team has the same-specification engine as the works Mercedes Formula 1 squad
Comments made by driver Felipe Massa during the Australian Grand Prix weekend had been interpreted as hinting that Williams did not have the same 1.6-litre V6 hybrid turbo engines as the Mercedes, but the team insists that this is not the case.
"We have no doubts over the parity of the engines from Mercedes during the Australian Grand Prix," Symonds told AUTOSPORT.
"We have a great working relationship with all the team at Brixworth and know how hard they pushed things to the limt to bring the best performance to Australia.
"HPP are constantly checking the data and all the power units are exceptionally close in performance.
"Our aim now is to continue developing the car to ensure we can fight Ferrari."
Engine freeze regulations mean that the engine specification supplied to the Mercedes customer teams should be the same - other than at times when upgrades are introduced and the four-power units per entry regulations create an offset.
Bob Fernley, deputy team principal of fellow Mercedes customer Force India, stressed that this is a contractual obligation.
"Yes, and the contract states that," Fernley told AUTOSPORT when asked whether Force India has engine parity.
"All fairness to Mercedes, they have always been straight with us."
Williams remains resolved to take on the works Mercedes team, and despite its quickest car being 1.391 seconds off pole in qualifying, performance chief Rob Smedley believes there is no reason why it will not be able to close the gap.
"It's a big gap, we should make no bones about it," he said.
"Mercedes is the benchmark so that's what we have to do, that's the level of excellence that we have to attain.
"The gap is big, but it's not insurmountable; we showed last year that we could develop the car as well or even better than others and we just have to carry on in that ilk.
"We are moving forward all the time and we just have to hope that we can close that gap down and eventually pass them."
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