The Potters thrashed Bolton 5-0 at Wembley two weeks ago in one of the most one-sided last-four clashes in the competition's history. It was a stunning result considering the teams were expected to be evenly matched, and Whelan hopes it will go some way to shaking off Stoke's image as a team that rely solely on set-pieces.
The 27-year-old said: "Winning 5-0 we've maybe changed a few people's minds but we know you're only as good as your last game so we'll put that to the back of our minds. It was a great day and a great occasion but we haven't done anything yet. It's only a semi-final, we want to win the final."
The Wembley date with City on May 14 will be the culmination of three years in the Barclays Premier League where Stoke have consistently defied expectations under manager Tony Pulis.
Whelan hailed the achievements of the Welshman, who began his second spell with the Potters in 2006 before winning promotion to the top flight two years later.
"He's done really well, and since I've been at Stoke we've improved every year, points-wise and position in the league," said Whelan, a £500,000 signing from Sheffield Wednesday in January 2008.
"To think this season we could finish in the top 10 and be in an FA Cup final, it's unbelievable.
"The manager would be the first one to say we've stuck together through thick and thin. Everyone's going to have their downs but it's how you react to that. We've reacted really well and hopefully we can keep doing that.
"It's been a big change over the last few years. We've become a team to be reckoned with and I don't think there's too many teams who want to be playing Stoke week in, week out."
Source: PA
Source: PA