Williams ran with what chief technical officer Pat Symonds called an 'experimental' front wing in preparation for the 2017 season during Friday practice for the United States Grand Prix.
The front wing will be 150mm wider as part of next year's rule changes, and Williams ran a version of its 2016 wing with the number of fences that channel airflow passing between the front wheels increased from two to four.
"Here and in Mexico we are running with an experimental front wing, but it's experimental rather than development, it's a bit of a correlation exercise," said Symonds
"We ran it in practice on Friday and we'll run it again on Friday in Mexico because we need to get a certain amount of data on it.
"It correlates well with what we are looking to do, so it's not an advantage to us this year, it's just a thing we want do try for next year."
Symonds added that the wide-ranging rule changes for next season mean most of the parts being worked on cannot be tried on a 2016 car, but the front wing is an exception.
"When you have incremental changes to the rules you are always carrying on in the windtunnel, developing a car," said Symonds.
"You might change the model number, but a lot of what you are doing is relevant.
"If you come up with something that is really good you say 'Sod next year! We'll get on with that now!'
"But then this year, what we're doing in the windtunnel isn't relevant really.
"Funnily enough, about a month ago we did something on next year's car that worked really well and we thought 'Crikey!'.
"We had never tried it on this year's model, so we just quickly put this year's model back in [the windtunnel] but thought 'That doesn't work at all'.