The Red Devils have set up a last-eight clash with the South Americans after recording a 2-1 victory against the USA on Tuesday.
It took Argentina until the end of extra time to claim a 1-0 win against Switzerland in their last-16 tie, and Wilmots is confident that his side can cause an upset against their South American opponents.
"There's a lack of balance in that team," ESPN quotes Wilmots as saying. "For once, we're not favourites, but we want to win. That's all the matters.
"We're going to make sure that we play well against a strong team, but everybody is a strong team at this level and every detail will make a difference.
"They play with five defenders, so we will have to be creative. I have everything in my head already, don't worry. We will deal with this Argentina as a team."
Belgium will be making their first appearance in the quarter-finals of the World Cup in 28 years this Saturday.