If the teams elect to effectively use the new upgrade however, they will both be forced to take grid penalties as a result, and F1i understands Toro Rosso will not use the new unit.
"We will have our new specification of power unit available to use in Austin," Renault's director of operations Remi Taffin said.
"The principal changes involve the internals of the ICE (internal combustion engine) to give improved power and efficiency. We know that introducing the new PU will incur a grid penalty so the decision to use it 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."
Renault's reliability woes have subsided in the last races while performance has also improved, so much so that Red Bull Racing has considered patching up its relationship with the French manufacturer in order to secure an engine supply vital to its involvement in Formula 1.
Regardless of whether the revised unit is used or not, Taffin is optimistic of the level of performance which can be potentially achieved by the Renault powered cars at the Circuit of the Americas.
"Whatever spec we do use, we are looking forward to Austin," Taffin added.
"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."
"There's very little not to love about Austin. The setting is impressive, the welcome is warm and the track is one of the best we visit all year. There are some very impressive corners and flowing complexes that challenge drivers, engineers and the technology we use."
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