McLaren's MP4-30 will "light up" on the track once Honda sort out their engine issues and the team figure out how to get more heat into their tyres, according to Ron Dennis.
After a disastrous start to the 2015 season that saw Fernando Alonso and Jenson Button struggle at the backend of the grid, McLaren have made progress in recent races.
Button finally opened the Woking-based team's points account at the Monaco Grand Prix and they took another step forward in Hungary when both drivers finished in the top 10.
Dennis, chairman and chief executive of the McLaren Group, believes Alonso and Button, who were fifth and ninth respectively in Budapest, were actually handicapped in Hungary due to problems in qualifying.
"I think what we took away from the weekend most is our pace," he told Motorsport.com. "We had problems in qualifying which masked the potential to be between 8th and 12th. And our race pace was good.
"We overtook a lot of cars and we had pretty good car balance. Now the work that we have been putting into not just the car but the engine will star to flow into the next few races.
"We will definitely have another step in Spa, and then I think it will get progressively better."
The problems with their Honda engine have been well publicised, but Dennis admits their failure to get heat into their Pirelli tyres is also holding them back slightly.
"One of the things that we wrestle with is the tyre temperature," he added. "We just don't have the level of overall performance to generate the heat in the tyre.
"I think once we get past the specific spot in relationship to getting the tyres to work – the car will light up.
"It occasionally happens in the race. There is still a long way to go, but we will get there."