The FIA have today banned the practice of changing engine mapping from qualifying to the race, a move which has been received with surprise by some of the teams.
Previously, teams could alter the settings of the engine between qualifying and the race, usually opting for a more conservative engine map for Sunday. Their qualifying engine settings would be more extreme, burning more fuel and maximising the exhaust gases over the diffuser. The practice is thought to have caused this year’s discrepancy between strong qualifying speed and relatively weaker race pace from teams such as Red Bull.
The news comes ahead of the ban on off-throttle use of blown diffusers from the British Grand Prix and is thought to be a measure to pre-empt teams’ circumvention of that ban.
Renault’s technical director James Allison is reported as saying that the ruling will cause all teams to adapt their designs.
“The FIA’s note will cause all teams, whether or not they use a blown floor, to change their operation,” said Allison, as quoted by Autosport.
“The headline changes for the Silverstone GP are as follows: when the driver lifts his foot fully off the throttle pedal, then the ECU maps must be set up so that the engine [to all intents and purposes] closes the throttle – previously it was possible to configure the engine maps to leave the throttle open and reduce the engine power by other means.
“Furthermore, when the driver lifts fully off the throttle, the ECU maps must be configured to cut off the fuel supply to the engine this is intended to prevent so called ‘hot blowing’ where the energy of the exhaust gas is increased by combustion.”
The Englishman went on to say that it he could not predict how much it would affect his team’s performance.
“It is not easy to judge the effect of this change on our competitiveness. The loss for each blown floor car will come from two separate effects how much downforce will you lose and, in addition, how much will the loss of this downforce upset the balance of the car.
“All blown floor cars will lose downforce under braking as a result of these new restrictions. Some teams will lose more and some teams less; it is hard to know exactly what relative loss LRGP [Renault] will suffer.
“However, it is possible that we will suffer less on the balance shift side of the equation because our forward exit exhausts produce their effect quite near the middle of the car. This means that as the exhaust blow waxes and wanes, it does not really disturb the aero balance of the car too much.
“With a rearward blower, the downforce from the exhaust is all generated at the rear axle. As the new rules reduce the blowing effect on corner entry much more than corner exit, it is possible that the rearward blowers will tend to suffer more nervousness under braking and more understeer on exit as a result of the new restrictions. We will find out in Silverstone.”