Toro Rosso tested the Honda engine in 2018 ahead of the Red Bull switch in 2019 and there had been concerns over power and reliability with vibration issues a concern during pre-season testing. However, they have since been put to bed with the team being seemingly pleased with the early signs of the engine.
In an interview with Motorsport-total.com Verstappen said there were no “big question marks” ahead of the first grand prix in Australia.
"It's a completely different engine in terms of how it works and how to accelerate, downshift, and upshift.
"So far, I only knew the Renault engine and now this one is trying to draw positive from both, because not everything was negative in the previous year.
"You learn from it and you try to share your opinion, you explain your own ideas on how to improve something, that's how it works.
"There is virtually no limit, they are trying their best to win - hopefully this season,” added Verstappen.