The team, who ousted Martin Whitmarsh as principal in January after their worst season since 1980, have failed to score a point in three races despite having the same power unit as dominant Mercedes.
Jenson Button and Danish rookie Kevin Magnussen finished 11th and 12th in Spain last Sunday while former McLaren driver Lewis Hamilton chalked up his fourth successive win with Mercedes, who have won every race so far.
Boullier told reporters that the team, whose form has plunged since Magnussen was second and Button third in the Australian season-opener, was starting "from quite far back" but had everything in place to recover.
"I think the real question about how capable we are at catching up and how fast we can catch up will be from Austria to Silverstone," he told reporters.
"I'm not saying we're going to win at Silverstone, I'm saying we'll know more about our capability to catch up by these races.
"I don't think we will shift our focus onto 2015," he added. "But it's possible that we will draw a line after Silverstone and we may go with more radical concepts."
McLaren are switching to Honda power units next season.
The team's home British Grand Prix on July 6 is the ninth round of the 19 race championship, and McLaren failed to score a point at Silverstone last year.
The second most successful team in Formula One history, after Ferrari, failed to secure a single podium finish in 2013 and last won a race in November 2012.
They are still without a title sponsor and the run of three races without a point is their worst since 2009 when they drew a blank in Spain and the three successive races. They are currently sixth in the constructors' championship.
Boullier hoped to see an improvement in Monaco next week.
"We have seen very, very significant progress in the wind tunnel in the last few weeks, so I think we need to just understand where we are, where we want to go," said Boullier.
"Monaco could be not bad for us. Our car is well-balanced in low-speed corners and very driveable, so Monaco could hurt us less."