Renault F1 updates for United States GP aimed at improving power

As outlined by Autosport on Monday, the French manufacturer has used the bulk of its remaining 2015 tokens on internal combustion engine (ICE) and turbo changes.

A Renault statement confirms that the "new specification of power unit [is] available to use in Austin", having reached dyno targets.

However, it remains to be seen whether the upgraded unit will be adopted by Red Bull, based on the grid penalties it would incur.

Sister squad Toro Rosso is understood to have ruled out using the new unit this weekend.

"The principal changes involve the internals of the ICE to give improved power and efficiency," Renault director of operations Remi Taffin said.

"We know that introducing the new PU will incur a grid penalty so the decision to use will be made in full consultation with the teams.

"At this point of the season obviously points are crucial so if circumstances allow then we will use on track.

"Our reliability has been good in the last three races and performance more in line with our expectations; both our teams just need a clean weekend to show the improved potential of both packages."