Sergio Perez says Force India is not concerned it won't be receiving a supply of Mercedes' updated power unit before the end of the 2015 season, saying it is 'not that big a step forward' at the moment.
Mercedes spent the entirety of its remaining in-season development tokens on updating its power unit ahead of the Italian Grand Prix with a view to making a head-start on 2016 development, with works drivers Lewis Hamilton and Nico Rosberg making use of it from Monza.
However, the manufacturer said at the time it was uncertain it would be rolling out the update to its customer teams of Williams, Lotus and Force India before the end of the year in an effort to focus on reliability.
Despite this, Perez says Force India isn't concerned about not receiving the latest engine since Mercedes doesn't regard it as 'a big step forward' in its current guise.
“At the moment all we have heard is that they are checking reliability to see if it is working well and from there we will see. We are not planning to get any of the full specification for the rest of the year, so hopefully next year we can.
“What we have heard from Mercedes is that it is not that big a step forward, is the team is not too concerned about getting the engine.”
Only Nico Hulkenberg and Nico Rosberg have suffered notable engine problems during the 2015 season, with all other Mercedes-powered cars getting only their fourth and final power units at this weekend's Russian Grand Prix.