Renault unsure about using mass damper

The French car manufacturer had been set to refit the devices after being told that there was little risk of them being punished at this month's FIA Court of Appeal hearing if the mass dampers were declared illegal.

"Firstly, we received notification on Monday that the FIA will recommend to the Court of Appeal that teams who have used the mass damper in Hungary should not have retrospective penalties applied when the hearing takes place between before Turkey," said Renault's director of engineering Pat Symonds earlier this week.

"In light of this, we will use the device again in Hungary."

However, another letter from FIA technical delegate Charlie Whiting to the teams explaining the FIA's position has left Renault unsure about whether to run with the mass damper.

Whiting's latest letter, which was sent to all the teams, explained the full background to why the FIA believe that mass dampers are illegal. It specifically expressed concerns about mass damper use extending to the development of twin chassis in F1.

That letter, allied to the threat of a possible protest from rival teams if they run the device, means Renault will now make a late call about whether they run with the mass damper.

A team spokesman said: "We are considering our position."

The Hungary Race Stewards will now also get involved in the situation after Whiting rejected the Scuderia Toro Rosso cars at scrutineering on Thursday because they were fitted with mass dampers.

A decision on that matter is expected imminently, and could play a factor in whether Renault decide to refit them.