The FA Cup winners came out comfortably on top against the Premier League holders courtesy of fine goals from Santi Cazorla, Aaron Ramsey and Olivier Giroud at Wembley.
The Gunners were two goals to the good by half-time, with City coming back into the game early in the second half before Giroud effectively ended the contest on the hour mark.
Arsenal's Premier League campaign begins on Saturday with a home clash against Crystal Palace, live on Sky Sports, and Wenger was delighted with the way his side prepared for the clash with the Eagles.
He told reporters at Wembley: "I felt we had a complete performance in the first half and we stuck together well in the second half.
"Today was good preparation - it was important to win today and now we focus on a very different game next week.
"It was important for our confidence to win the game, we also had a quality performance and that is comforting for me.
"I have more attacking options than I had for a long time, that's for sure. We are a strong squad."
Wenger saw centre-back Thomas Vermaelen complete his move to Barcelona earlier on Sunday, and had nothing but praise for his former skipper.
The Arsenal boss also hinted that he will look to bring in another defender in this transfer window, despite being impressed with new arrivals Calum Chambers and Mathieu Debuchy.
He added: "Vermaelen behaved outstandingly last year - I am grateful for him and I wish him very well.
"If I can find another centre back I will do it. You make your position with your performances."
Regarding Chambers and Debuchy, he concluded: "For a 19-year-old, he had an outstanding performance today. He was very impressive. Debuchy was excellent.”