Toto Wolff has admitted Mercedes is pushing the development of its 2018 car to the limit.
Italy’s Corriere dello Sport claims that with Ferrari and Red Bull closing in, Mercedes has pushed the limits with the performance parameters of the new car.
The report says several exhausts have broken on the test rigs at Brixworth during race simulations, apparently due to vibrations emitted by a shorter and smaller gearbox.
Team boss Wolff said: "Nothing ever goes completely to plan, because you’re always trying to explore the limits and make the car as light as possible.
"But I would say that we had a good winter. There were no big dramas even if the stress is always there," he added.