Zaha was signed by United in a £15million deal in January, before returning to Palace on loan to spend the remainder of the season in the Championship.
He is now due to join up with his new United team-mates at Old Trafford after helping Palace to a 1-0 victory over Watford in the Championship play-off final.
The winger's dart into the Hornets penalty area in the 15th minute of extra time ended with Marco Cassetti bringing him down before Kevin Phillips dispatched the resulting spot-kick.
And Long hopes United will be tempted to release Zaha to Palace as the Premier League new boys may be able to provide regular game time for the player following the Wembley success.
Long said: "They might want him to get experience in the Premier League playing for us rather than maybe not playing for them. I don't know, of course.
"We probably will ask."
Palace manager Ian Holloway also revealed after the match at Wembley that he would love to have Zaha back at his disposal next season, although he knows David Moyes will probably want to keep the young forward.
"I think he (Moyes) would be silly to give me him back. Now we're up it might be realistic but who knows?
"He will know the task he's got. Mine will be staying up, his will be winning every week. Good luck to him and good luck to us."
Long's co-chairman, Steve Parish, also feels that Zaha will now stay at United and backed him to play a key role under Moyes.
He said: "I think Wilf should go and have his chance with Manchester United. I think he has earned that. We certainly won't be making representation.
"I would hate him to go anywhere else if that was what they were going to do. Me, personally, I think he is good enough for their side."