Haas' partnership with Ferrari can be a "double-edged sword", according to the team's chief designer Rob Taylor.
Haas entered F1 this year with a controversial Ferrari tie-up, which included an engine supply and as many parts as the regulations allow. While that has saved costs and man hours for the American team it means Haas has limited time to understand the parts and integrate them into its own plans for the VF-16.
Taylor admits this creates a headache for Haas from a design perspective.
"It causes its own little problems," Taylor said. "We absorb a lot of information from Ferrari but they only give it to us when they know it so all the parts we purchase, we don't really have a good visibility of them ahead of time.
"Normally you've got some idea of the concept you're going to be employing before you ever get to the full-blown design. With the agreement we have with Ferrari we don't see some of the parts until they're quite well thought out and coming towards fruition, so it's like a double-edged sword.
"You don't have to do the work, but you've got to react to somebody else's work later than you normally would."
Taylor says Haas' biggest challenge comes when fitting parts designed for Ferrari's SF16-H to its own 2016 challenger.
"Our biggest anxiety isn't to do with 'Will it fit when it's finished and installed?' It's 'Can you get it in there? Can you get your pinkies in?' The little bit of the front rocker for instance is a bit of a tortuous route.
"We're building our chassis and they're building their chassis with the nuances of a millimetre clearance. It's not whether the whole rocker is going to work in the car, it's the stupid question of 'Oh dear, it won't go in, find a mechanic with smaller hands!'"