Renault allows F1 teams to unlock more engine performance in China

The works Enstone outfit, Red Bull and McLaren can now use higher power modes for longer than was the case in Australia and Bahrain.

Despite Daniel Ricciardo's energy store failure in Bahrain Renault felt the engine had proved itself sufficiently reliable when running more conservative modes to allow the step-up in performance.

"We are doing what we said we would be doing," Renault Sport boss Cyril Abiteboul told Autosport.

"We wanted to confirm reliability, which we've done so far.

"We have had an incident with Ricciardo, but the reason is still unknown, as we are talking.

"Whether it was chassis or engine related, we're still unsure of the root cause. It was an electrical issue, which obviously impacted the energy store.

"Apart from that, combustion engine-wise and ERS, it's pretty OK. We are obviously pushing the envelope in terms of usage and operation of the engine.

"It's starting to have some impact, in particular on a track like this, which has a certain sensitivity to energy management."

Renault plans to make another step when the second round of power units come on stream, with a major MGU-K upgrade among the items in the pipeline.

"As far as hardware is concerned if we are sticking to our plan, it's for power unit number two, which is not coming for a while," he said. For the time being it's more energy related.

"We'll have some more stuff coming from the ICE, and also with the fuel a bit later, depending on the teams, as we're not using the same fuel [supplier]."