"For China, we will be preparing and transporting two slightly different engine specifications, one of which is a small gain over Monza, and the other a larger gain," said Renault's engine guru Rob White.
"Between now and Thursday, the dynos in Viry will be working day and night on track simulations.
"The data gathered will be analysed, to orientate our choice of engine for the race."
For the first time this season, Renault lost the lead in the constructors' championship after a disappointing Italian Grand Prix, which was won by Ferrari's Michael Schumacher.
The Italian squad are now three points ahead of Renault with just three races remaining.
Schumacher is only two points behind Fernando Alonso in the drivers' standings, after the Spanish driver retired with a broken engine from the Monza race.
White said the team had found the cause of the failure and is confident it will not happen again.
"We have found the exact cause," White added. "For obvious reasons of technical confidentiality, we do not wish to go into details, but it was a sudden failure in the bottom end of the engine. Our analysis of that engine, and our efforts to reproduce the failure, have allowed us to fully understand the problem.
"It is always presumptuous to say that we are 100% confident there will be no problems - nothing in this business is ever 100% certain. The pressure is on for both us and Ferrari, as any reliability problems at this stage of the season would be catastrophic.
"We know that we have been rigorous in our analysis, our testing and our risk management in finding the appropriate solution to the failure in Monza. We will not race a solution that we do not have full confidence in."
il dit,
nous amenons deux specifications, qui sont testées actuellement et jusqu'au dernier moment nous choisirons quelle evo adopter, l'une et une legere amelioration de monza, l'autre une grosse evolution, viry travail jour et nuit, et nous dira quelle est la meilleur solution au dernier moment!
nous savons d'ou vient le probleme, je le dirais pas ici, mais c'etait sur le cul du moteur, notre analize et nos efforts pour reproduire la casse "pendant les essais' nous a permit de comprendre completement le probleme! c'est resolu!