McLaren: F1 power unit changes needed but difficult before 2028

The timelines involved mean hardware changes to the Formula 1 power units are all but impossible for 2027, but McLaren argues they are still needed to improve the series

McLaren F1 team principal Andrea Stella believes further changes are required to the power unit regulations, but the timescales are pushing any changes to 2028 rather than next season.

F1 recently agreed a first set of refinements to improve the qualifying spectacle and reduce the extreme closing speeds witnessed over the first few races of the 2026 rules era. The Miami Grand Prix last weekend was the first to run under the tweaked ruleset and appeared to bring modest improvements, with the jury still out on the precise impact of changes to the energy management until F1 heads to more energy-starved circuits later this spring.

More sporting tweaks are not ruled out if necessary but it is understood more significant improvements will require changes to the actual hardware of the power unit. An increase in fuel flow would squeeze more horsepower out of the internal combustion engine and alter the energy balance away from the electric engine while a bigger battery means cars don't run out of energy so quickly. A less disruptive change would be for the FIA to lower downforce levels a little bit, because cars going slower through the corners means less energy is needed.

However, unless F1 stakeholders reach an agreement through the proper power unit governance structure, any structural changes to the power unit seem very unlikely before 2028 at the earliest given the timelines involved, and an increase in fuel flow is not something the current engines are built for. It would have a knock-on effect downstream on the fuel tank and chassis with a number of teams already planning to keep their existing chassis for next season.

McLaren's Stella, whose team runs on Mercedes customer engines, says the current formula needs an increase in fuel flow and a switch to bigger batteries, but admitted it would be difficult to push through for 2027."I think hardware adjustments to the power unit are needed to improve Formula 1 in general," Stella told Motorsport when asked for his view on the matter.They will have to do realistically with the fuel flow to increase the power output from the internal combustion engine.

I think they might have something to do with harvesting more power than the power you actually deploy, because you spend much more time to deploy electrical power than to harvest it. This can be rebalanced by harvesting to a higher power than we do today. 350 kW, 400 kW, 450 kW? And then I think we need bigger batteries.I see that from the power unit manufacturers’ point of view this is difficult for 2027 because the implication for the battery size and the implication for coping with the higher fuel flow, they are normally a longer lead time than the time available to go into the 2027 season.

Stella hopes the F1 stakeholders will finish discussions before the summer break so manufacturers have enough time to implement them for the 2028 season. "“I would urge that maybe this conversation needs to be finalised before the summer break to be in time to do it for 2028,” he said."Certainly I hope that's the case, because we have done a good job as an F1 community of constantly looking at improving the exploitation of the engine with what's available, I think we can extract more out of these regulations, but this will need some hardware tweak.

Toto Wolff, the Mercedes F1 boss, said he would not oppose some tweaks to improve the spectacle but argued the series is already in a good place at the moment.“Anyone talking about changing engine regs in the short term should ask himself about his way of evaluating Formula 1 at that point,” Wolff said following the Miami GP. A great race. Battle for the top spot, battle in the midfield. And it is lovely.

Can we adjust and optimise it in the mid-term? I think yes, definitely. We’d never be against making the show even better. I am thinking of Straight Mode. “I think we need a lot more straightline speed with the straightline modes.” We have to be brave enough to do that.”If we could wring a bit more performance out of the ICE… “Great, give us enough lead time so we can actually do it.

Asked when teams need to know what 2027’s technical regulations will be, Alpine team boss Steve Nielsen said: “Now… More fuel means bigger a fuel tank, means a different chassis. And not every team is planning to make a new chassis for next year, because with the budget cap you spend your money where the most performance is.

Maybe a new chassis is not where the most performance is. But of course if your fuel tank isn't big enough to take 10 or 20 extra litres you'd have to do it and you'd have to know that. “Very simple.There have been lots of changes to the regulations in the last few weeks. Hope it quiets down a bit. "But if we start to see big changes in the next few months, then for next year our ability to react will be stretched.”