McLaren has announced plans to build a new wind tunnel at its Woking headquarters.
For years, the British team has used the more updated Toyota facility in Cologne to develop its F1 cars.
But Andreas Seidl, the newly appointed McLaren team boss, says that will change.
"We are 1.5 seconds at least behind the top teams, and this is connected only to aerodynamics," he said at Paul Ricard.
"It is clear that the gap is largely due to not using our wind tunnel. Therefore, I am very pleased that it was decided to build a new wind tunnel at Woking.
"This is very important news for the team and it shows how seriously Zak (Brown) and the shareholders are to progress the team."
Seidl, formerly the boss of Porsche's ultra-successful Le Mans effort, says the tunnel will be built within two years.