Fernando Alonso ended up 12th overall in second practice for the Australian Grand Prix as improvements to the Honda power unit meant McLaren was able to get some decent running at last.

But with Honda's 2017 power unit clearly requiring more horsepower if it is going to challenge nearer the front, the Japanese manufacturer revealed that work was already underway on a revised engine.

The updated version will retain the split turbine and compressor concept that Honda has adopted for this season, but will feature hardware changes.

Honda hopes the engine can be ready before June – so could be introduced around the time of the Monaco Grand Prix, when teams are likely to switch to the second of the four power units they have available for the season.

Honda F1 chief Yusuke Hasegawa said that speed trap figures which put Honda around 9km/h down on rivals Mercedes indicated that power was an issue.

"The power difference is big," he explained. "To raise the power it is necessary to raise the combustion efficiency, but to do that you have to change the hardware of the current power unit.

"So I am developing an improved power unit, but it will take some time to complete. I would like to have it finished and in the car within two months."

Reliability steps

Although Honda suffered no major reliability problems on the opening day of action, the vibration issues that dogged the final days of testing have not been cured completely.

Furthermore, in a bid to minimise the oscillations, it is understood that Alonso and Stoffel Vandoorne have been asked to change gear in a different rev range – which is costing some laptime.

Hasegawa added: "The vibration was not that much of a problem today. However, there was a little bit at the time of the up-shift, so if we solve that then we may earn a little more laptime."

McLaren executive director Zak Brown said that his team took some encouragement from the progress Honda had made – but knew that getting more power was essential.

"Today was alright," explained Brown. "The reliability was good, but the speed was not where we want to be but it was better. I think some others had some issues, so I don't know if today is representative of where we will be tomorrow in qualifying.

"I hope so because 12th would be a little bit better than anticipated. But it was only free practice and day one. You don't know who turned it up and who was on what fuel load, but today was a good day."

Asked about the vibrations, he said: "They have been improved. But I think it is too early to say that things have been solved, because we haven't done a GP distance.

"But it was good that we got some good laps, more laps, than we had done in any one day. The drivers liked the car. Fernando and Stoffel said the car feels very good, looks good – now we just need to get further up the grid."

Additional reporting by Kunihiko Akai