Bortoleto and Hulkenberg admit Audi power unit loses performance in extreme heat

Gabriel Bortoleto and Nico Hulkenberg acknowledged ahead of the Singapore Grand Prix that Audi’s power unit loses outright performance in extreme heat — a limitation that emerged in Malaysia and is set to persist at Marina Bay, where the FIA has issued a heat hazard declaration forecasting temperatures of 31 degrees Celsius or above.

The admission is significant because Singapore was, on paper, one of the more favourable circuits for Audi. The Marina Bay Street Circuit is less power-sensitive than many venues on the calendar, which would typically narrow the gap to the leading engine manufacturers. But that theoretical advantage is being offset by the power unit’s sensitivity to high ambient temperatures.

Hulkenberg was candid about the scale of the problem during his Thursday media session. “I think Malaysia brought some new things to light and these climatic conditions are not so favourable for our PU at the moment,” the German said. “We definitely had some struggles on that side and obviously here it’s more of the same.”

When asked whether the issue stemmed from cooling — with Audi forced to open bodywork and sacrifice aerodynamic performance — Hulkenberg was direct: “No, I think we suffer from power.” The implication is that the engine itself is producing less power in the heat, rather than the car simply running a compromised aerodynamic configuration to manage temperatures.

Bortoleto echoed that assessment. “I would say that right now, especially in the last races, it’s our biggest limitation,” the Brazilian said. He added that Audi’s current package is “something decent” for a first season, but that improvements in drivability and thermal performance remain necessary steps.

Despite the candour about the current shortfall, Bortoleto was emphatic that Audi will close the gap. He pointed to the manufacturer’s track record in the DTM and at the 24 Hours of Le Mans as evidence that its engineers in Neuburg are capable of building class-leading power units.

“If I trust them? Absolutely. I think they can fix it,” Bortoleto said. “These people in Neuburg have built the best engines in other series that they have taken part in in the past, and I have no doubts they’re going to do the same in Formula 1. We just need to give them time.”

Hulkenberg, meanwhile, tempered expectations for the Singapore weekend. “It is a less power-sensitive circuit on paper, for sure, but my personal expectations are not too high for the moment,” he said. The team is led by Allan McNish, who took over as team principal as Audi continues its phased entry into the sport.