Optimal burn

What we aspire to do is put those [fuel] droplets in exactly the right place within the combustion chamber

Since Formula 1 entered its V6 turbo-hybrid era in 2014, the series’ internal combustion engines have been improving on thermal efficiencies of around 40 per cent at the start of the rules cycle, with the latest now exceeding 50 per cent. Add in the contribution of the hybrid system, and the overall efficiency of modern F1 power units is now at an extraordinary 55 per cent, whilst power output has also increased over the last eight years, now crossing the 1,000bhp barrier.

Why has this engineering achievement not been better promoted by teams or F1, particularly in today’s environmentally-aware arena? ‘One of the tragedies of the current formula is that when we went to Melbourne in 2014 we should have been saying, “look at these engines, they’re now using two thirds of the fuel they used to a few months ago!” But someone said they didn’t like the sound of these V6s, and instead that became the topic,’ says Pat Symonds, F1’s chief technical officer.

A fast yet controlled combustion process is the most effective way to achieve high thermal efficiencies

To fully understand the depth of this achievement, we first need to comprehend what ‘efficiency’ actually means. ‘We use a regular unleaded gasoline that is optimised for this power unit and, if you combust that, you turn it from hydrocarbons into heat energy,’ explains Andy Cowell, managing director of Mercedes AMG High Performance Powertrains.

Mechanical work

‘If you could capture all of this heat energy and turn it into useful mechanical work, that would be