Sebastian Vettel has refused to publicly compare Mercedes’ Formula 1 power unit to Ferrari’s👍 out of respect to the two engine manufacturers.

The four-time world ✃champion previously drove Renault and Ferrari’s power units during the turbocharged hybrid era but following his switch to the rebranded Aston Martin team for 2021, he has now had his first experience of Mercedes’ class-leading engine.

Mercedes has won every single championship on offer since the current generation of power units were introduced in 201ꦑ4 but following his first time driving the German manufacturer’s engine, Vettel was keen not to disclose any detail.

Asked to describe how the Mercedes power unit compared to Ferrari’s, Vettel replied: “It’s obviously different but I’m not going to compare, just out of respect to different manuf♑acturers.

“It’s something that I’ve never done in the past and I won’t do noꦉw.𒅌”

After turning in 51 laps on a productive first day of pre-season testing in Bahrain on Friday, a gearbox issue restricted Vettel to just 10 laps on Saturday morningꦑ.

The German said he is eager to “make up lost ground” when he gets back in the c⭕ar for the final time before the start of the season on Sunday af๊ternoon, with Vettel still adapting to the AMR21.

"🦩The last 24 hours have certainly been very busy for myself, for everyo🔜ne in the garage, for the whole team,” Vettel said on Saturday afternoon.

“Unfortunately we didn't have a ver💙y productive morning [on Day 2], we had an issue with the gearbox we had to change and that cost a bit of time.

"That's what happened and unfortunately we didnꩵ't get a lot of laps in. So this morning was not of great use in terms of track time.

"Yesterdไay [Day 1] though was very interesting. The car feels very promising but there's still a lot of things I need to get used to.

“The car is different to what I ran [last year] and it's a different power unit꧙ as well so everything feels a bit different and takes a little bit of getting used to."