Mercedes denies F1 has become an engine-dominated formula in 2014

The Mercedes factory team has won nine of the 11 grands prix held so far in 2014, while customer squad Williams has helped ensure nothing but a car powered by a Mercedes engine has qualified on pole this year.

Mercedes-powered teams also occupy four of the top six spots in the constructors' table, but Mercedes GP technical chief Paddy Lowe does not believe his marque's dominance is a sign the new hybrid rules introduced for this season have made engines the fundamental factor in car performance.

"These cars are about system performance, not individual elements," Lowe told AUTOSPORT.

"It's about how you put it all together. It's the power unit, the efficiency of the power unit, the aerodynamics, and the manner in which they're all put together.

"It's the collective efficiency of that package from a power, aero and suspension point of view, as well as a weight point of view.

"Our car is very quick. There are other cars running that power unit that aren't as quick, so it's a whole system."

Lowe said he expected much of the power difference to Ferrari and Renault would have been down to short-term issues experienced by the other manufacturers, but reckoned constant improvements by his own team might have masked the gains made by its rivals.

"A lot of the deficit has been on the power unit side, and you wonder how much of that is fundamental and how much is short-term issues they need to learn to manage," Lowe added.

"I would have expected more would have been short-term and been overcome.

"It's difficult to know because we're pushing in so many different areas and you don't know which areas they're pushing in.

"We've been concentrating on our own programme and we keep pushing hard to improve the car race by race - what turns out, turns out, but I'm happy we're managing to maintain a good gap."