Coventry will be without Marlon King and James McPake for clash.
Striker King is serving the second game of his three-match ban having been sent off in the 1-1 draw against Ipswich on New Year's Day.
McPake, meanwhile, was forced off early in Monday's 2-1 defeat at Barnsley and has since been found to have two fractures of his lower back which will rule him out for months and not weeks.
The exact length of the centre-back's rehabilitation is not yet known but it is likely he could require surgery and may possibly miss the rest of the season.
Fellow central defender Ben Turner is a couple of weeks away from his return from a lengthy knee injury, leaving manager Aidy Boothroyd with a defensive decision to make against Palace.
But the City boss is left in no doubt about the importance of the cup encounter, he said: "Some people don't put full-strength teams out and I think you have to respect the cup. We'll be picking a team that's strong and a team that is looking to win the game. The club has won it, there's a big history around here and one of my ambitions is to stop people talking about 1987 and start talking about a different year that is successful."
Crystal Palace will check on Darren Ambrose and Pablo Counago ahead of the game.
Midfielder Ambrose has a leg injury and striker Counago is struggling with a hamstring problem, and caretaker boss Dougie Freedman rates them both 50-50.
Full-back Julian Bennett's loan has expired but centre-back Anthony Gardner has extended his deal until the end of the season.
Midfielder Alex Marrow has completed his permanent switch from Blackburn but he may not manage to shake off an ankle knock in time for the clash.
Better news is the return of centre-half Claude Davis, who played a full 90 minutes for the reserves this week after recovering from a hamstring strain.