The Renault F1 team has bolted a more powerful V10 into its RS24 for the San Marino Grand Prix this weekend, but will the new powerplant stand the punishment of the Imola circuit?

The Renault F1 team has bolted a more powerful V10 into its RS24 for the San Marino Grand Prix this weekend, but will the new powerplant stand the punishment of the Imola circuit?


Both Ferando Alonso and Jarno Trulli have been testing engine and aerodynamic modifications to the RS24 since the Bahrain Grand Prix.


"The new engine is a good development in all areas," Trulli said recently. "There is more power, better torque and it is more driveable."


As far as the aerodynamic modifications were concerned, the Italian commented: "The stopwatch confirms the wind tunnel readings. It is definitely a step forwards."


But if Renault is to reap the benefits of its development work at Imola, the RS24 – in particular its engine and transmission – would first have to last for the duration of San Marino race.


Those infernal kerbs!


Imola will be a baptism of fire for Renault’s new V10 – the San Marino Grand Prix consistently sees one of the highest mechanical retirement rates of the year. The circuit has historically taken its toll on dampers, transmissions and engines.


"The Imola’s kerbs make the circuit very hard on transmissions, said Pat Symonds, Renault’s director of engineering. “62 per cent of all retirements (at Imola) in the past three years have been engine or transmission related. When a car bounces over the kerbs, transmissions get damaged not in the initial impact but through the second part of the chicane, when the cars are often at full throttle, and land in this state.


When that happens, the transmission effectively works like a spring, loading up when the wheels land and grip, before needing to release this energy. The impact produces extremely high shock loads on the transmission and can lead to failures of both the gear ratios themselves and the driveshafts," he added.


Torque key to success at Imola


“Drivers use the kerbs as much as possible to set a quick lap time. Aside from the implications for the car’s suspension, engines often over-rev when cars bounce over kerbs”, Denis Chevrier, Renault’s head of engine operations, said.


“As soon as the powered wheel is no longer in contact with the ground - when the car launches from the kerb after initial impact - the phenomenon is similar to declutching. The engine no longer encounters any resistance, and the engine speed increases dramatically as a results. The risk to reliability varies according to the amount of time the car spends 'in the air', and also the engine speed at the time when it launches,” Chevrier explained.


Every engine has a specific tolerance to over-revving, and those pre-established limits are what we must work within in order to ensure engine reliability, even if it means sacrificing a little performance, the Frenchman said.


However, drivers spend much of the lap at full throttle - beginning in second gear on the exits of the chicanes.


“This means a strong torque curve is important, and the car also needs very good traction. In this first respect, the improvements brought with the “B” spec will certainly be an advantage throughout the performance range,” Chevrier added.

Original article from Car