MONZA (Italy) • Bernie Ecclestone stepped into Formula One's tyre row on Thursday to deliver an embarrassing rebuke for Sebastian Vettel and his Ferrari team.
In a rare intervention, the F1 chief executive chided teams who ignored safety tips from Pirelli to push their tyres to the limit.
Behind the message was a stark warning to Ferrari and four-time world champion Vettel, after his expletive-laden outburst in the wake of his tyre burst at the end of the Belgian Grand Prix.
Vettel was noticeably muted at the official press conference for the Italian Grand Prix on Thursday when he praised Pirelli's probe into the puncture which robbed him of third place in Spa-Francorchamps last month.
Perhaps a word in Vettel's ear from the most powerful man in F1 did the trick.
By the time of the press conference, the driver had read Pirelli's written response. It said Ferrari might have been riding their luck asking their man to push his tyres for 30 very fast laps around the gruelling Spa circuit.
Pirelli said their tyres suffered an "exceptional number of cuts" throughout the weekend, caused by debris on the circuit.
They had asked the FIA, the governing body, to ensure that the track was cleaned thoroughly the night before the race.
But the main conclusion, published and accepted by the FIA, was that "the remaining tread thickness on Vettel's rear tyres was approximately 30 per cent at the time of failure, making the tyre more susceptible to damage from even a small piece of debris".
Much is at stake in this row, with Pirelli's contract as official suppliers coming to an end next year.
Jean Todt, the FIA president, appears to favour a swop to French-made Michelin tyres but Ecclestone wants to keep Pirelli.
A statement from Ecclestone's Formula One company read: "Pirelli provides strong guidance to competitors... (who) should heed Pirelli's expert advice when setting their race strategies and tactics.
"And if they do not, it is at their own risk."
Lewis Hamilton, the world champion who yesterday clocked a best lap of 1min 24.670sec to outpace Mercedes team-mate Nico Rosberg by six-tenths of a second in the opening free practice for tomorrow's Italian Grand Prix, described short-term measures to increase tyre pressure at Monza by an unprecedented five pounds per square inch as potentially "a disaster". He said it would increase wear and decrease grip.
Pirelli have recommended changes to pressure and camber for tomorrow's race. Drivers expect an increase from 18 PSI (pounds per square inch) to 22 on the front and 21 on the rear, or even as much as 23 and 22 respectively.
"In terms of putting the pressure up, I don't think it's the right way," Hamilton said.
"I don't think any of us have tried five PSI more on these tyres because they're not designed to have five PSI more.
"We would be moving out of the optimum range of the tyre, we'll be using a different part of the tyre which means there will be more wear, less grip. It's going to be a disaster. So I hope they don't put five PSI more. A couple is okay."
McLaren's Jenson Button also wondered why cuts in the tyres needed an increase in pressure.
However, Rosberg, who also suffered a puncture in Belgium, welcomed Pirelli's advice.
THE TIMES, LONDON, REUTERS
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