Renault F1 engine technical director Rémi Taffin has ensured that the French manufacturer's dismal power unit reliability issues which dogged its season last year, are a thing of the past.

Renault's performance in pre-season testing in Barcelona was encouraging, both from the perspective of its works team than from that of its customer Red Bull.

While the performance level of its power unit will gradually improve over the course of the 2016 season, the man in charge of development at Viry-Châtillon, Rémi Taffin, believes it won't be at the expense of reliability.

"Reliability is under control," said Taffin.

"We had some issues with a turbo but we knew there was a potential risk there. We're working on a just-in-time basis, so many parts destined for Melbourne have not yet been produced.

"Obviously, we need to find the proper balance between performance and reliability. We wanted to start the season with a more efficient product, but which would be especially reliable and 'transparent' for the driver, offering a better comfort in driveability.

Taffin stressed that the specification used in Barcelona would be run in Australia, while an upgrade is planned in June.

"The specification we’re using now will be used in Melbourne. The engine works as expected, every bit gives what it was expected to give.

"We got everything we thought we would have on the engine, anything we measured on the dynos, any gain in driveability, etc.

"In the last two years we lost a bit of faith in what we were doing and testing. Now, we can work on this steady specification, we can build up on that.

"We hope to introduce an evolution in June which is forecasted as a milestone on our path to 2017. We would prefer substantial progress, worth at least half of a second, rather than small incremental steps worth a few tenths."

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