In an interview for BMW WilliamsF1 team BMW Motorsport Director Mario Theissen discussed the recent Australian Grand Prix and the next challenge for the BMW P84/5 engine in Malaysia.

How did the new BMW P84/5 engines cope with the first Grand Prix of the season?
"In Australia, we experienced no problems whatsoever with the BMW P84/5 engines. After the race, both engines were absolutely okay. Nevertheless, we will equip Nick Heidfeld's car with a new engine, as the new regulations allow for this when a driver doesn't make it to the finish.

With Mark Webber's car however, we will contest our very first GP weekend with a car that hasn't been equipped with a new engine. This is going to happen in the hottest race of the year, Malaysia. At Sepang, the engine will have to cope with two big challenges: doubled mileage and extreme thermal load."

How can BMW prepare for the extremely high temperatures associated with the Malaysian Grand Prix?
"During pre-season testing, it's impossible to simulate tropical conditions, particularly as the conditions at the south European circuits were rather chilly over the part few months.

To combat the high Malaysian temperatures, we will see all the teams using additional or bigger cooling inlets at the front of the side- pods and outlets such as holes, slits, chimneys or exhaust pipe casings. Furthermore, the engines will be cooled whenever the car is stationary. As soon as a car enters the garage, the mechanics will affix dry ice equipped fans to the side-pod inlets."

Once the warm-up lap is completed and the cars are stopped on the grid, engine cooling is reduced. How demanding is it on the engines?
"This situation - no air stream and the sun beating down - can be critical, as the water temperature can rise extremely quickly. To avoid the use of costly high-pressure systems, the FIA has stipulated that the cooling circle must be equipped with a pop-off valve opening at a pressure of 4.5 bar. Should this happen while waiting for the start, the engine loses water that cannot be replaced. No question about it, the BMW P84/5 will have to withstand a true endurance test."