Toro Rosso driver Pierre Gasly admits it is "important" Honda produces a reliable engine for he and teammate Brendon Hartley to use when pre-season testing begins in Barcelona at the end of next month.

The junior Red Bull team agreed to take on the Japanese manufacturer for 2018 after McLaren ran out of patience following three years blighted by poor performance and reliability, switching to the Renault units Toro Rosso had been using for this season.

Entering his first full season in Formula 1, after replacing Daniil Kvyat at last year's Malaysian Grand Prix, Gasly knows there will be a lot to do to ensure the Italian team heads to the first race fully prepared.

"The important thing at the test will be to have a reliable package so we can do as many laps as possible and get a good understanding of where we are with the car, the engine and how the package is planned to evolve," the Frenchman said.

"There are only eight days of testing before Australia and that really isn't very much."

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Executive director at former partner McLaren, Zak Brown, has backed Honda to start meeting the expectations the Woking outfit had when they teamed up again in 2015.

"There's a certain way you have to operate in F1 and I think that's something they now recognise," he said appearing at the Autosport Show began on Thursday.

"Maybe some more F1 experience, direct experience, is probably what they [Honda] were lacking most, it certainly wasn't effort, resources - the facility is great, and I think they'll get it right.

"It's more a way of working. I think they'll get there, but three years was as long as we could wait."