Williams plans to introduce a new short nose at the second Formula 1 grand prix of the season in Bahrain.
The Grove-based team launched its 2016 challenger with last year's nose and has run it throughout pre-season testing.
Speaking on Friday, deputy team principal Claire Williams said: "We have a new nose coming for Bahrain."
The crash tests have yet to be done but the team is confident they will be completed in time for the Sakhir event on April 1-3.
As testing drew to a close, Williams said she was pleased with the work the team has carried out over the last two weeks.
When asked if it can take the fight to Ferrari and Mercedes, Williams said: "I hope so.
"I hope we have done enough to get in the mix because people want to see more teams at the top.
"It will be tough. Everyone knows the might of Mercedes and Ferrari and what they are able to put into their programmes is somewhat greater than what we are able to.
"I believe we have done a good enough job but we won't know until Melbourne."
When asked the same question, Williams technical director Pat Symonds added: "As a team, we have set objectives and the numeric ones we can assess we have achieved.
"Whether that is enough, we'll find out over the first four races."
Williams said the target for the season was to win a race on pure pace.
"Would I be disappointed if we finish third [in the championship]? No," she said.
"My business head says no and my heart says yes because I want to win a race, that's what I want for us.
"I don't just want one and I don't want it to be a fluke or a one-off or because someone else has not done what they needed to do.
"I want us to win a race."