Brawn GP is the third team whose diffuser design for its 2009 car has been questioned by F1 rivals including Renault's Flavio Briatore.
That is the suggestion of the Cologne newspaper Express, following Briatore's comments that the rear diffusers of three unnamed teams "do not conform to the regulation".
It is reported that Brackley based Brawn, who have astonished the formula one world with their test pace in the wake of Honda's withdrawal, has taken the controversial Williams and Toyota-like diffuser interpretation even further.
Express claims the BGP001 design effectively links the floor with the diffuser in a curved fashion, with the result of radically increased rear downforce.
Ferrari team boss Stefano Domenicali on Saturday was quoted as dividing F1 teams into two camps: those (including Ferrari) who applied the 2009 rules "to the letter" and those who took "a different approach".
"The FIA has to dissipate any doubt; let's hope they'll do it fast and clear," the Italian added.
