Renault chief technical officer Bob Bell has said the team "know what to do" in order to be more competitive in races this season.
Nico Hulkenberg and Jolyon Palmer both qualifed in the top 10 at the Bahrain Grand Prix, but the former fell from P7 to P9 while Palmer was last of the finishers.
“We need to find more pace on Sundays, we just lack race pace,” Bell told Motorsport.com. “We knew that going into the race.
"We’ve got a reasonable view on where we’re losing and why it’s happening, so we’ve just got to deliver on the bits that will restore that. It’s a combination of tyres and aero, and getting them to work under all circumstances.
“We know what we need to do. What we haven’t been able to do is demonstrate it on track, deliver the bits to the track, and deliver on that upgrade. That’s the next step.”
“The basic pace of the car is there. You couldn’t put it where we put it in qualifying if it wasn’t.
Bell is also confident that they are making decent strides since last last season and are doing everything they can in order to keep heading in the right direction.
“We’re in much better shape than we were a year ago," he added.
"We’re not where we want to be, we’re not where we planned to be, but we are getting there, one step at a time.
“There’s an ongoing engine development programme which will bring bits to the track, with different engine tranches when we feel comfortable.
"At the moment the engine performance isn’t the issue, it’s the chassis performance that’s holding us back.”