Eric Boullier is happy enough with Lotus' rate of progress, even if the second half of the 2012 campaign has been slow-going at times.

The Norfolk marque looks comfortable sitting fourth in the constructors' championship, almost 100 points clear of Mercedes in fifth – and that would represent the achievement of their key goal for the season.

However, with Kimi Raikkonen's drivers' title charge falling flat and the team without a top four finish in the last two races, Lotus have seemed unable to kick on and deliver on the clear promise the E20 has had all season.

'As I have often said, it is important not to get carried away in this paddock,' said Lotus team principal Boullier. 'When things are good, people have to remain calm and remember what the initial objectives are. When times are tough, being overly pessimistic does not help either.

'With the E20, we can rely on a tidy and reliable racing car and I think we have surprised a few people this year, but we need to progress one step at a time.

'We've always said that our target this year was to finish fourth in the championship. I'm not saying that we won't chase Ferrari (in third) until the end of the season, or that we don't want to, I'm just putting things back into context.

'People should remember where we're coming from. Pushing too hard or reviewing our objectives in the middle of the season could only have a negative effect. This is not a lack of ambition, it is down to experience: rushing things in F1 will – more often than not – mean collapsing.

'We'll keep pushing; we're doing our best and the 2012 season has been good for us so far. We'll then see where this takes us.'

After a ban and heavy criticism for his racing in Spa, Romain Grosjean returned with a calm drive in Singapore. And Boullier hopes both of his drivers will be at it full pelt in Japan this weekend.

'Kimi is a special animal. His race craft is always fantastic; he manages to extract 100pc from the car on Sunday and to make the most of every opportunity,' added Boullier.

'Who would remember, today, that he's been out of this sport for the last two years? Now, the priority is to score points regularly with two cars because the constructors' championship is really important to us.

'Romain has shown in Singapore that his raw speed is still there. He did not make any mistakes and will be able to build on this experience in Suzuka. Something tells me that the end of the season will give us quite a few nice surprises.'