Vitaly Petrov thinks Lotus Renault GP may have to wait until the Japanese Grand Prix to discover the full potential of its latest upgrade package, with the team staggering its introduction over the next few races.
The team has struggled on low-speed circuits so far this year, which leaves it cautious about its prospects for this weekend's race in Singapore, but Petrov is most optimistic about its chances for faster tracks coming up. As part of its development push, Renault is introducing tighter packaging of its rear bodywork in Singapore, while further updates have now been postponed until Japan.
Speaking ahead of first practice, Petrov said: "Maybe with [softer] Pirelli tires or maybe on this track our car will be quick, but before at low speed and with traction our car is not fantastic. For Suzuka, maybe we will have a good car and maybe we will bring some surprise things, but here we don't know."
Petrov has also revealed that the team recently discovered the performance of its car was susceptible to change depending on bodywork attachment.
"Sometimes the bodywork, if you fix it wrong, like if one nut is tightened a bit stronger, then the bodywork can get shaped in a different way, so all the aerodynamics are completely different," he said.
"The mechanics now try to be precise how they fix it, because our car looks like it is super-sensitive [in this area]. We understood this a few races ago and it is quite interesting. For example, we found that in Monza and in Spa, when the mechanics did something like fixing the floor or other parts of the car, it completely changed the aero and we lost 10 points, or even 15-20 points [of downforce]."