Mercedes F1 team still trying to solve overheating “unanswered mystery”

Both George Russell and Lewis Hamilton found their power units running too hot, and from early in the Bahrain race they were told to adjust engines modes and their driving in an attempt to keep temperatures under control. They eventually finished in fifth and seventh positions.

Mercedes customer Williams suffered similar issues, but McLaren and Aston Martin had no problems.

Teams adjust their cooling capacity on the basis of expected race day ambient temperatures, and Allison admits that Mercedes is still trying to understand what went wrong in Bahrain.

“That was actually the biggest unanswered mystery from the weekend,” he said. “We were substantially hotter in the race than we expected to be.

“It’s always something of a gamble choosing your cooling level for a given race weekend, because you’re having to take a bet on free practice running what the weather is going to be like on a Sunday.

“Normally you’re also making a few corrections for different power levels and other things that can vary between the race and when you’re doing your practices.

“This particular weekend was one of the weekends where we had to make the fewest guesses possible, since we’d already run this cooling level loads of times in winter testing, and we’d already run these power levels in winter testing as well as free practice.”

Allison says the team hit problems despite getting the ambient temperature correct.

“The temperature that we got on race day was incredibly close to what we predicted it would be,” he said. “Therefore we had all of the circumstances to make an accurate prediction for where the [PU] temperatures would be.

“The fact that we got it wrong by more than one or two degrees is extremely unusual, and quite punishing, because once the cars are above the limit that the engine guys will guarantee the engine to, we just have to back off the car.”

Allison noted that once it happens it’s hard to maintain performance, with tyres also affected.

“We have to back off the throttle at the end of the straights, we have to turn down some of the modes of the engine just to make them survive,” he said. “That just robs you of lap time, it robs you of tyre temperature, and it just ruins your race effectively.

“So it isn’t solved yet. It’s one of the things that we got a programme of work this week in the factory to…