Toro Rosso technical director James Key says the team will retain its low drag philosophy with its 2015 car.

While Toro Rosso went for a low drag design with its car in 2014, part of that decision appeared to be out of necessity due to the weakness of the Renault power unit. However, when asked if the team would be retaining that idea with its 2015 car, Key replied: "We have because we believe there's a bit more to be found there."

Explaining the trade-off between drag and downforce, Key said Williams - another team to opt for a low drag design this season - had shown what is possible with a stronger power unit.

"As you pile downforce on so it becomes more difficult to get a gain from it. It's a very non-linear thing and efficiency is always important but even more so when you're operating at high-downforce levels. These cars, it's difficult to tell when they're going to flatten out from a downforce perspective. We haven't at the moment, I'm sure it will come. But when you do it's drag reduction and I think what Williams has done has been extremely effective.

"So we'll have to see. It's power unit related. We tend to have a little bit of a low drag philosophy because when you come to Sunday you know that's going to be pretty important unless you're sitting at the front. So it's a good thing in my eyes. But then you can still do that if you hit peak levels - let's say a Monaco level of downforce - if you're good there you can still come back and it's probably a nicer place to be. So the more downforce you get it's always better."