The Gunners could move seven points clear at the top of the table if they leave south Wales with a victory - something which United failed to do last weekend when Kim Bo-Kyung struck a deserved stoppage-time equaliser while City were beaten 3-2 at the Cardiff City Stadium in August.
Wenger, though, knows it will take a focused collective effort to get a positive result against Malky Makay's well-organised side.
"They beat City at home and they played a very good game against Manchester United where possession was 50-50, so that is the challenge for us - to do better than these teams," said Wenger.
"We have the warning of their performances against the big teams, so we are in a position where we have a difficult challenge, but also a very exciting challenge because we can do better."
Wenger continued: "Cardiff look to have good solidarity, good togetherness and fantastic support as well.
"They are all on the same wavelength in the team and are very efficient at home on set-pieces.
"Even on Sunday when they were 2-1 down against Man United, many teams could have thought 'okay, it is Man United, we will not come back', but you always had the feeling that they don't give up.
"You could feel that they would come back. They have that special attitude and belief in the side - and that makes them dangerous."
Wenger will have England full-back Kieran Gibbs available again after illness ruled him out of the midweek Champions League win over Marseille, which all but secured safe passage through to the knockout stages.
The Gunners boss expects his side to continue their momentum and lay down a marker for the likes of City, United, Liverpool, Chelsea, Southampton and Tottenham, all of whom do not play until Sunday.
"We have that opportunity we want to grab at the moment," said Wenger, who insisted he remained relaxed about ongoing talks with the club over their offer of a contract extension.
"We are in a position where we do not need to look too much at the other results, just at our results, that is a luxury and of course we want to take advantage of that."
The performance of Wales international Aaron Ramsey will again be key as he returns to face his former club.
Ramsey is enjoying a stand-out campaign, having scored 11 goals for the Gunners.
The Caerphilly-born 22-year-old has come a long way since leaving Cardiff as a raw talent in a B£5million deal during the summer of 2008 - with Makay describing Ramsey as "one of the best performers in Europe" on current form.
Ramsey also had the option to join Manchester United, while Everton were anther interested observer, but after a personal meeting with Wenger at the European Championships in Switzerland, the midfielder decided to instead further his career at Arsenal.
"I expect him to continue to improve. He is a young player and of course there is a lot more to come from him," said Wenger.
"Aaron Ramsey has no limitations in his improvement and he can be a complete midfielder, efficient defensively, efficient offensively - that is what real football players are."
There has been some debate in recent weeks as to who is the Premier League's best striker.
Wenger feels the likes of Liverpool's Luis Suarez - a summer transfer target - and Manchester City forward Sergio Aguero offer their own talents.
However, in 10-goal Olivier Giroud, Wenger is in no doubt he already has a leading frontman of the highest order.
"Giroud is among the best, all of them have different qualities," he said.
"He is more of an English-type striker - he uses well his body and his link play with others (is good).
"His physical presence in the box is massive, especially with the type of team we have, with smaller, technically-mobile players, so to have that kind of presence up front is important."
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