Lewis Hamilton ‘disappointed’ in FIA if Mercedes compression ratio behind Melbourne speed

Mercedes stunned rivals with its one-lap performance at the Australian Grand Prix, displaying a 0.8-second advantage over its closest challengers.

Ferrari’s Lewis Hamilton said he hopes that the “compression ratio” saga – which Mercedes found its name attached to in pre-season – is not the root cause of that Mercedes advantage over one lap. If so, Hamilton fears the damage done before the new hot engine test comes into force could be significant.

Lewis Hamilton on Mercedes: ‘Hope it’s not this compression ratio’

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Mercedes stormed to a front-row lockout at the season-opener in Melbourne, with George Russell on pole ahead of Kimi Antonelli.

Ferrari grew more competitive on race day, but could not prevent a Mercedes one-two, as Charles Leclerc narrowly saw off Hamilton to complete the Melbourne podium.

All eyes will soon turn to China to find out whether Mercedes can replicate that advantage that it had in qualifying trim.

Red Bull’s Isack Hadjar qualified third in Melbourne, but was just under eight tenths slower than Russell. Leclerc was just the other side of that deficit.

“I don’t understand it exactly,” Hamilton said of Mercedes’ one-lap heroics, as he spoke with PlanetF1.com and other accredited media.

“Yeah, they didn’t show that they could turn it up in testing, and now they’ve got this extra power from somewhere, and we need to understand what that is.

“I hope it’s not this compression ratio thing.”

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What Hamilton refers to is a major talking point of the pre-season. Initial reports pointed to Mercedes and Red Bull Powertrains as the manufacturers who had found a loophole in the new engine regulations, one which allowed them to increase the newly-lowered 16.1 engine compression ratio when running hot.

Mercedes eventually found itself isolated against rival PU manufacturers, and the FIA confirmed the introduction of a hot engine test, as previously, the compression ratio was only measured at ambient temperature.

That was originally set to come into effect from August, but has since been brought forward to June.

As reported by PlanetF1.com’s Thomas Maher back at Bahrain testing, depending on who is speaking, the performance advantage from this closing loophole ranges from negligible, to several tenths per lap.

“Hopefully it’s just pure power, and we’ve got to do a better job,” Hamilton continued.

“But if it is a compression thing, then I will be disappointed that the FIA allowed that to be the case, that it’s not to the book, and I will be pushing my team to do the same thing so we can get more power.”

Since this new hot test is coming in June, it was pointed out to Hamilton that Mercedes would only have a few months with whatever advantage it may or may not have.

“If they have a few months of that, then the season’s done,” Hamilton replied, before clarifying: “Not done, but seven races, a few months, you lose a lot of points with a second behind in quali.”

Additional reporting by Mat Coch

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