Lewis Hamilton wants less drag and more power from the 2020 Mercedes Formula 1 car, admitting "it's not been a great year" for engine development by his team.
Engine superiority was a cornerstone of the start of Mercedes' dominant run in the current F1 era, but its advantage has steadily been eroded and Ferrari is now regarded as the benchmark for straightline performance.
Hamilton said he had complete faith in Mercedes turning around what had become a clear weak point.
"We've got time for next year. I think it's not been a great year for us in terms of the great issue, in terms of our engine development," he said.
"I think it's been a really hard time for the guys, they've been working as hard as ever but it's just not been as successful in that department, as I say.
"Plus it's quite draggy but we've had great reliability and hopefully that remains the same and that's still something to be really proud of, of course.
"We have, obviously, still won the constructors' championship but we'll push to try and maybe reduce the drag a little bit but also increase power for next year.
"So they're fully onto it and I have all the confidence in the world that we'll be able to make some sort of step into the next season."
Hamilton admitted that his fruitless pursuit of Sebastian Vettel's Ferrari for second in the closing laps of the Japanese Grand Prix had emphasised to him how far Mercedes was trailing for straightline performance.
He pointed out that overtaking the Ferrari was impossible even with "the tow, with DRS and maximum power and everything" plus the Mercedes being on fresher tyres.
Hamilton added: "It's incredible how quick they are. It makes it very, very difficult, even if you've got the advantage of the tyre.
"But I think it's cool anyway, it provides interesting racing."
Vettel felt he had also been helped by slipstreams from the cars they were lapping in that battle, but acknowledged he had taken full advantage of the possibilities Ferrari's straightline edge offered.
"I think we have an advantage in a straightline, I tried to play that, it worked," he said.
"I tried to slow down a little bit and slow down in the areas I could afford to and speed up in the places leading onto straights where he could have been a threat."