Felipe Nasr is expecting engine gains from Ferrari to boost Sauber by almost half a second per lap at the Belgian Grand Prix this weekend.
Sauber started 2015 brightly but faded across the remainder of the first half of the season, as it was out-developed by more well resourced rivals.
The squad will receive the engine upgrades from Ferrari which was first used by the manufacturer squad in Canada and Nasr is sure that Sauber will benefit from the tweaks.
"Here, I'm expecting [the updates] from Ferrari to be around a four tenths gain so it’s a decent time for Spa, if you’re bringing something new here an engine is useful for extra power," he said.
"But I wouldn’t rely all on it yet as Spa is quite a unique track in terms of straight line speed and cornering speed, you need a balance in between things."
Nasr nonetheless expects Sauber's package to suit the circuit, and believes that any opportunities for further top 10 finish will come in Belgium or at the next round in Italy.
"We always struggle to reach high downforce so we should be in the range for this track, it’s a track I like and it’s a track where the weather plays a lot," he said.
"So we need to wait and see, if there’s an opportunity that might appear it’s here and Monza, to return to the points."