Jenson Button is confident McLaren can make up a "good chunk" of time this weekend but says it won't be as much as a second per lap.
Starting the season very much on the back foot given their new relationship with engine partner Honda, McLaren have yet to score a single World Championship.
They have been close on two occasions with Button finishing 11th in Australia while Fernando Alonso matched that result in Bahrain.
The team is hoping to change that this weekend in Spain where Button reckons their upgrades will be worth "good" time out on track.
"There are upgrades in every area, we haven't come here with a second of lap time because that doesn't happen in Formula One these days even if you started where we did," he explained.
"It is a good chunk, we have got upgrades with the power unit and aerodynamically but also mechanically there are a few things.
"It is getting to the point where it is very difficult to have the same amount of progress percentage-wise.
"The whole middle-pack is very close and there for the taking so I'm looking forward to that challenge – this circuit should suit us a bit better than the last race in Bahrain – it will certainly suit me better, I might be able to go around this time."
And although the 2009 World Champion believes points could be on offer this weekend, he insists just scoring a few points is not the Woking outfit's ambition.
"If we put our weekend together we know there is a good chance of scoring points.
"If we score a point we are not going to be jumping up and down with joy – that is not our aim. It depends on what other people do.
"If every other car on the grid has a good weekend it is going to be very difficult to score points but Fernando out-qualified a Red Bull and Toro Rosso (in Bahrain) – it just means people aren't getting their weekend together.
"The gap to the front is important to us, if we finish 11th but the gap to the front is eight-tenths smaller that is the thing that matters to us rather than just getting P10."