Sergio Perez believes the high-speed demands of Silverstone may disguise the scale of the improvement that Force India will make with its upgraded car at the British Grand Prix.
The team is introducing a major revamp of its Mercedes-powered challenger, with new wings, nose, floor and bodywork, aimed at lifting its performance.
But despite some positive talk after the post-Austrian GP test about the changes, Perez believes the true benefit of the new parts may not be clear to those outside the team because the outfit may not appear to make a dramatic leap up the grid.
"It might be transparent for you [to explain the situation] that if we don't do great on Sunday, and you say 'it didn't work'," Perez told the media on Thursday.
"But if we had our original car as we had in Barcelona, which is a similar track in terms of high speed demands, where a lot of downforce is required, then we were going to struggle massively with our car.
"Also don't forget that we are coming from an engine track [in Austria] where we saw some benefits for having the Mercedes engine and not so many corners.
"Here, we should see some progress and I am sure about it, it is just that we might [only] close the gap to the cars in front. But to be able to fight them at a track like this will already be a big step forward."
Uplift in fortunes
Despite his caution about Silverstone prospects, Perez is full of hope that the remainder of the season will deliver improved fortunes.
"We are all very optimistic when we look at the numbers that it looks quite promising, but at the same time we are very realistic.
"Everyone will say that an upgrade is not just about putting it on the car and getting on with it; it needs some processes and needs some work to understand how to take the maximum out of it.
"Hopefully tomorrow we can have plenty of mileage to see where we are."
Lotus and Toro Rosso main target
Perez believes that his team's main challengers this weekend will be Lotus and Toro Rosso.
"I am surprised about Lotus because when we see the simulations they seem to be half a second quicker than us," he said.
"For some reasons, like reliability, they haven't been able to exploit their full potential. So I think they are a big threat.
"And Toro Rosso, they have a mega car and I think when we go to do downforce circuits like here they should be strong."