It is clear that there is growing frustration in the pitlane regarding the 'legality' of the Toro Rossos.

The Italian-based outfit is the only team using V10 engines this season, the result of a deal done when the (now) Austrian owned team was Minardi, owned by Australian Paul Stoddart.

With a limited budget which meant Stoddart was unable to purchase V8s for his team, the other teams agreed that special dispensation should be given to the Faenza outfit allowing it to use V10 powerplants, though these would be 'restricted' in terms of power in order that there was no advantage.

Then, Stoddart sold out to the wealthy Red Bull company, which, though it could have afforded V8s, opted to stick with the previously agreed (restricted) V10.

For some time there has been concern along the pitlane that the Toro Rosso would enjoy an advantage over its rivals, with various teams hinting at possible protests.

Speaking yesterday, McLaren boss, Ron Dennis, made it quite clear that he was unhappy. "All teams who had committed to running V8s very much appreciated that there was going to be an advantage from running V10s and going down an equivalency route," said the Englishman. "We undertook with each other, signed a document that undertook to each other that we would run V8s, in other words, permitting, in writing, to run V8s.

"The team that was given the concession to run V10s was Minardi, and it was given the concession for financial reasons, not for performance reasons, and there are several parameters of the engine that must be addressed when achieving an equivalency. Horsepower is one, and it is something that absolutely you can achieve, but a V10 engine will always give more torque and you cannot tweak the engine due to all the air restrictors and that sort of thing. It might or it might not form an equivalency, but it's important to remember that the reason for the engine issue in the first place was for cost reasons, not a formula by which people had a choice.

"That formula has been contracted out deliberately by people who wanted V8 engines," he added. "That is a clean, clear, analytical statement of fact."

Ferrari's Jean Todt was in agreement: "When it was decided to allow some private teams to have access to V10 with a restrictor we informed the FIA that we could object depending on the outcome of the championship with the car, so I am confident it is going to happen," said the Frenchman. "Of course we cannot avoid having agreements like this one, but I am confident that the FIA can do the right thing."

However, Gerhard Berger, who has recently taken a 50 percent stake in Toro Rosso, stuck to his guns: "I have to say, we took over a team from Minardi. We had a contract with the team and with the engine. Should we be penalised for using the engine or should the FIA try to put it into a fair position."

Meanwhile there is mounting concern over the legality of the Toro Rosso chassis, the STR1, which to all intents and purposes in the 2005 Red Bull chassis, itself based on the 2004 Jaguar, with a few bits added on.

Should the Toro Rossos qualify or finish higher than many deem realistic, expect the protests to begin, with Midland most likely to raise the legality of the chassis.