Honda could be poised to overtake Renault and cease having the least powerful engine in Formula 1.
Auto Motor und Sport and Marca report that in Russia, the Japanese carmaker will introduce the third version of its 2018 power unit.
The publications say that Honda's Spec 3 engine will be 35 hp more powerful than its current one, relegating Renault to last place in the power stakes.
Toro Rosso's Pierre Gasly and Brendon Hartley will take penalties for fitting the new engines at Sochi, but that will leave them clear to push for better grid positions at Honda's home Japanese Grand Prix a week later.
Reports in Italy recently said that Ferrari has broken through the 1000 hp barrier with its latest engine, a full 27 hp ahead of Mercedes with its 1005 hp power unit.
Renault then currently stands at 950 hp, compared to 930 for Honda.
Red Bull is switching from Renault to Honda power for 2019, joining the junior team Toro Rosso in using the Japanese-designed power units.
"They are pushing hard - we have confidence in what we see," said Red Bull boss Christian Horner.
"The investment that we see going into the programme, the quality of personnel that are involved, things are very much moving in the right direction.
"Only time will tell, but I think you'll inevitably see more changes this year which is all part of the development process for 2019 and beyond."
