Former Renault F1 driver Jolyon Palmer reckons Red Bull are keeping plenty of tricks up their sleeve ahead of next week's test in Bahrain.
Red Bull's new RB18 got fans talking at the first test in Barcelona when Max Verstappen pulled out of the garage sporting a number of unexpected and radical technical innovations on his car.
The car featured aggressive new sidepods, with plenty of solutions across the floor, as the team look to claw back as much downforce as they can following major winter regulation changes.
But they are not done yet, according to Palmer, who expects more surprises in Bahrain when testing resumes on 10 March.
The teams will spend three days on track at the Bahrain International Circuit perfecting their cars before the attention turns to the opening race of the new season, the 2022 Bahrain Grand Prix.
Speaking to Formula1.com, Palmer said: "[Red Bull] seem to be in a decent position overall, even if they acknowledge there is plenty more to do with the car.
"But as yet, I'd say they've maybe kept the most hidden of any teams – so they will be well worth watching in Bahrain."
Mercedes could show true pace in Bahrain
While Palmer expects Red Bull to reveal some extra secrets in Bahrain, it is Mercedes which he has tipped to bring the most upgrades.
The Silver Arrows had a drama-free test in Barcelona and left Spain happy with their work.
Palmer continued: "It was fairly metronomic as usual from Mercedes in racking up the mileage without serious mechanical issues, as well as getting on with the pre-season rituals of practice starts, pit-stops and a semi-race sim from Lewis Hamilton on the final day.
"Porpoising, which affected all the cars to some extent, seemed to be particularly harsh on the Mercedes on the opening day, and the drivers weren't particularly happy initially. Throughout the three days, it looked to improve, as did their lap times, with the help of the softest C5 tyre.
"George Russell looks immediately settled and accomplished alongside Hamilton.
"This was a decent start for the reigning Constructors' champions and of all the teams, the feeling is that Mercedes could introduce the most upgrades next time out in Bahrain, and showcase their true pace a little more."
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