Having finished third in the opening race of the year in Australia, Vettel went on to win the second race in Malaysia as he outpaced Lewis Hamilton and Nico Rosberg. Third place in China last weekend leaves him second in the drivers' championship and Vettel says the level of success has been hugely encouraging with further team changes still to be made.
"There are still a lot of things, obviously I wasn't here last year, so there is still a lot of change going on," Vettel said. "Some things are in place, others are not, but are due to be in place sometime soon.
"So far, as I've said many times, the atmosphere is great, people are happy, including myself, and the results have been phenomenal for us as a team. The ambition is there to do better, to catch Mercedes, even if it is at this stage very ambitious. For sure, that's the target for myself and the whole team."
With Vettel's win in Malaysia coming in hot conditions, the four-time world champion believes Bahrain will not play in to Ferrari's hands quite as much but still expects to be able to challenge Mercedes.
"The only problem is the sun goes before we start racing, otherwise it would be significantly hotter.
"I don't expect it to be that hot. Obviously Malaysia was extreme, but Malaysia is always extreme. For here I expect to be in a good position. So far this year, no matter the conditions, the ambient temperature, track temperature, I've always felt comfortable in the car.
"It seems to work in all sorts of conditions - dry or wet, hot or cold - so we should be in reasonable shape. We still need to confirm, it's still early, so that's the most important thing, that we are right behind Mercedes, and ideally a little bit closer every time."
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