Haas says it needs to be within 0.5s of Ferrari

The American team's form fluctuated dramatically from race to race and it ultimately finished eighth in the constructors' championship.

Haas, which received engines and non-listed parts from Ferrari, is hopeful it has created a more stable platform for the VF-18 as it bids to make up ground in its third campaign.

"It's no secret we use a lot of Ferrari equipment, so we're using them as our baseline," said team owner Haas.

"We need to be within a half-second of the Ferraris in order for us to be competitive.

"We weren't last year. I would say we were a second to a second-and-a-half slower than the Ferraris.

"Overall, we were maybe two seconds off the pole qualifiers, so we need to knock a second off that if we really want to be competitive."

Haas was in contention to finish sixth in the constructors' championship last year but finished 10 points adrift of Renault and six shy of Toro Rosso.

However, finishing eighth for the second year in the row was a solid result for a new team and Haas said the way the outfit has acquitted itself has earned it respect from rivals.

"Now we're just one of the teams, to the point where if we're in front of Lewis Hamilton or whoever, they don't go, 'Who are these people?'," he said.

"They know who we are. I think it's good. In two years, we've survived.

"We've shown we can compete at this level, and the teams around us were all within a few points of sixth, seventh and eighth there at the end of the season.

"That was an interesting place to be, and I'm sure the teams in front of us were very happy that they finished in front of us because now it's like they have another competitor to deal with."

Haas admitted the 2017 campaign was "more difficult" because the "competition was more intense".

He added: "The first year it seemed like we had more teams that were having challenges.

"It seemed like in the second year a lot of those teams sorted out their problems and all of a sudden they got a lot faster.

"The spread between the top cars and the bottom cars when we first started was four to five seconds, and now it's down to three seconds. The field is tightening up and everyone is getting better."