Wenger's men, who picked up a surprise 1-0 UEFA Champions League victory at Borussia Dortmund on Wednesday thanks to a second-half Aaron Ramsey goal, head to Old Trafford this weekend sitting top of the Premier League, five points clear of closest rivals Chelsea and eight ahead of United.
But the 64-year-old believes that the usually tense affair will feel very different without former United boss Ferguson in the opposite dugout, and he has stressed that it is too early to judge the Scot's replacement, David Moyes.
"It will be a bit strange without Sir Alex Ferguson there on Sunday," said Wenger. "My relationship with Sir Alex will be a bit more peaceful and a bit more serene.
"It's too early to tell the difference under (David) Moyes. He has shown great competence at Everton."
Arsenal have not won at the home of the Premier League champions since September 2006, but Wenger believes that Sunday's clash could prove an indicator of how far his side have come.
"It's still one of the benchmarks of the season where you judge how strong you are," he continued. "But, as well, people analyse everything and draw conclusions after the game.
"We had periods where we did very well at Old Trafford and recently we have not done so well, so it's a good opportunity to show that we have improved.
"Our target is to go there and win the game."
Meanwhile, man of the moment Ramsey believes that Arsenal can keep up their title challenge, despite United striker Wayne Rooney claiming it was too early to take their bid seriously.
"We had a fantastic run-in last season and, after the disappointment of the opening game of the season (a 3-1 defeat to Aston Villa), we managed to build on that," he said.
"If we can do that now and keep it going up until Christmas then we know that we have the ability to compete."
