Why Formula 1’s 2027 engines could exceed 50% efficiency and improve the racing. F1 targets higher efficiency and better racing with 2027 engine plans.

For those familiar with the limitations of internal combustion engines (ICE), the idea of reaching a thermal efficiency of over 50% might sound like pure utopia. However, in the world of Formula 1, this is already a proven reality. The sport previously boasted efficiency values exceeding 50% during the previous regulatory era. While those figures may have dipped slightly under the current 2026 framework, the recent announcement of a power rebalance for 2027 has effectively set a new benchmark for next year’s power units.

F1 to reach 450 kW of ICE power through a joint effort

Currently, with the combustion power limit capped at 400 kW, the thermal efficiency derived solely from fuel usage sits at approximately 48% (based on a fuel energy flow of 3,000 MJ/h). For 2027, the FIA is planning to introduce modifications to the maximum energy flow allowed from the fuel. If the goal was to reach the newly established 450 kW target ( a significant 50 kW increase) through fuel energy alone, oil companies would need to achieve a flow rate nearing 3,375 MJ/h—a value that is likely beyond current reach. This raises the critical question: where else can improvements be found?

The answer lies in a coordinated evolution. While the FIA will increase the energy flow of the sustainable fuels, the teams themselves will work to extract more performance by increasing the combustion efficiency within the cylinders of the ICE. To put the scale of the challenge into perspective: if the manufacturers had to find that extra 50 kW without any help from their fuel partners, they would need to reach a staggering 54% thermal efficiency.

Restoring the spectacle for 2027

As noted, this will be a collaborative effort between fuel suppliers and engineers, but we can already state with certainty that ICE efficiency will once again climb above the 50% mark. By shifting the power ratio—reducing the electrical requirement to 300 kW (down from the current 350 kW)—the cars will become more potent and consistent during both qualifying and the race.

The primary benefit of this 60/40 power split is the reduction of “clipping” and excessive energy harvesting, which has been a point of contention for drivers this season. With more constant performance throughout each phase of the weekend, the on-track action is set to become more intuitive and aggressive. For the fans, this technical pivot means one thing: a better show. By prioritizing the internal combustion element, F1 is ensuring that the sound, the speed, and the pure racing spirit remain at the heart of the sport in 2027.

The move to a 450 kW internal combustion target for 2027 represents a significant admission from the FIA that the initial 50/50 power split was perhaps too ambitious for the current state of energy recovery technology. By leaning back into the efficiency of the ICE, F1 is not only solving the “super-clipping” issue that has frustrated drivers like Max Verstappen and Lando Norris but is also pushing the boundaries of what is chemically possible with sustainable fuels. This technical “course correction” proves that even in an increasingly electrified world, the thermal efficiency of a racing engine remains the gold standard for high-performance engineering.

With the electrical deployment being scaled back to 300 kW to make the cars more “flat-out,” do you think this technical retreat is a win for the sport’s entertainment value, or a missed opportunity to pioneer even more aggressive hybrid technology?