The report belongs to Germany's Auto Motor und Sport, who also claims that both Toro Rosso drivers used 6-race old power plants during the Friday action at Istanbul. That would explain the STR4 poor performances during the first two Practice in Turkey, as both drivers finished the 90-minute sessions in the rear of the field.
As argued by team manager Franz Tost himself, “after 1400 kilometres, the power (of the engine) diminishes dramatically.” Although he did not confirm the use of 6-race old Ferrari engines, the reports goes on to assume that the power plants fitted into the Toro Rosso STR4s last Friday were no less than 2,500 km old.
Although they didn't manage to do a great job on Saturday either, there was clearly a lot more pace for the STR3s than in the previous day.
The same reports says that Ferrari are actually using the Toro Rosso outfit to test the longevity of their engines. Given the new engine rules for the upcoming season – mainly focused on prolonging their life – setting an early base for the development of their power plants for 2010 is looked upon as top priority for the Italian manufacturer.
Also, both teams would benefit from the aforementioned “experiment”, as Toro Rosso is believed to renew their engine deal with Ferrari for their 2010 campaign.