Mercedes have suffered a 'little setback' on 2019 engine – Toto Wolff

Mercedes chief Toto Wolff has said the team has suffered a "little setback" on its 2019 power unit concept, as it looks to continue its dominance following a fifth consecutive Constructors' and Drivers' title this year.

Next season brings with it a raft of technical rule changes aimed at improving overtaking, but to achieve this, downforce has been cut by implementing a simplified front and rear-wing, as well as other smaller changes.

Wolff however remains optimistic this loss can be recovered, admitting the team have had to increase their winter development targets to ensure they remain ahead of their rivals.

"The rules have been changed. Normally the aerodynamics and the downforce should be less but the rumours you hear from the paddock is that people have been able to recuperate lots of that," he said during a sponsor event.

"So there is a tremendous development race that is happening as we speak in finding downforce, reducing drag and of course the engine is a very important part, and adding more horsepower to the engine. So we are setting ourselves really ambitious targets.

"We have actually increased the targets six weeks ago because we heard some rumours that others were doing so well, so the slope...we increased the final point for the first race where we need to be in absolute lap time. We are still on the slope."

It's not unusual for manufacturers to introduce new engine concepts in order to maximise the development potential, but in doing so, Wolff says Mercedes have suffered a setback as those potential gains have yet to be realised.

"We've had some good weeks in the windtunnel, we've had a little bit of a setback on the engine side where we believed the new concept would deliver a little bit more, but these guys are very ambitious like all of us and so I'm optimistic.

"But you will never know. We will know when the first qualifying session gets under way in Melbourne."

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