A new wheel nut design was the cause of Felipe Massa's pitstop problem that cost the Brazilian fourth place at the recent German Grand Prix.
Massa entered the pits ahead of Red Bull's Sebastian Vettel but a delay cost him the place to the world championship-leading German.
Ferrari's head of track operations Diego Ioverno explained that the team, in the race for faster pitstops in the no-refuelling and multiple tyre-stop era, has been experimenting this year with new methods and equipment.
He said that at Silverstone, a new wheel nut design contributed to Ferrari performing the fastest overall pitstops.
"Then in Germany we were again using this new wheel nut, which does work better, but the system is still not perfect and, at Felipe's last tyre change, we lost the connection between the wheel nut and wheel nut gun, which cost us around one and a half seconds," he confirmed.
"So we have more work to do on perfecting it."