Suzuka: Vettel dominated in the Red Bull

As Sebastian Vettel closed the championship gap to Fernando Alonso to just 4 points with wins in Singapore and Suzuka, it had emerged that his RB8 was equipped with a new top speed-boosting system.

"As with all these things, there's never a silver bullet and I think it would be very difficult to say the car's performance here is purely down to a rear wing," team boss Christian Horner said in Japan.

"I think we've made progress in all areas and it's about chipping away at the detail."

Indeed, writing in Der Tagesspiegel newspaper, correspondent Karin Sturm said Williams' technical boss Mark Gillan also suspects something else was in play.

"I will have to analyze precisely the data of the race with all the relevant times," he is quoted as saying.

"Maybe then we can see what they've done."

Former F1 driver and now RTL commentator Christian Danner suspects Red Bull has found a sweet spot within the new exhaust layout regulations.

"This sort of thing is almost always about the aerodynamics," he said, "and with today's cars most of all with the various subtleties of the different exhaust solutions."