The England youngsters have already beaten Davey's men 22-19 in the Six Nations and 23-14 in this tournament, but a victory on Sunday means the Welsh side finish ahead in the final Cup rankings.
"We're disappointed with our performance against England last week and we're pretty happy to have a chance to fix that," Davey said.
"It was a poor game - there wasn't a lot of rugby played - and we have to pick up on our continuity play if we're to win on Sunday."
The long-serving Under-21 coach said he would be "pretty pleased" with a fifth-place finish, given how young his squad are and the fact he lost skipper Richie Pugh to the senior team on the eve of the tournament.
"They're a young bunch of guys and they're a tight group who have played well as a team," he said. "Eighteen of the 26 are eligible for next year's World Cup and four of the guys are eligible for the next two tournaments."
Davey said national coach Mike Ruddock's decision to take Pugh on the tour of Argentina and South Africa was the right one - despite the fact the Neath-Swansea Ospreys flanker never got on to the bench.
"It has to be the right decision," he said. "If he's the next guy in line, he had to be on tour in case he got the chance to get on.
"I think Richie will have learnt a lot from the tour and he now knows how close he is."
Wales go into the fifth-place playoff on the back of a hard-fought 29-21 win over France in Edinburgh on Wednesday.
Promising Neath fly-half Matthew Jones was the key player for Wales, and his long-range goal-kicking kept their noses in front during a tense second half after France had led 11-6 at the break.
No 8 Gavin Quinnell bulldozed his way over the try-line to give Wales a one-point lead after 70 minutes, and Cardiff winger Chris Czekaj scored in the final play to secure the victory.
Fullback Matthew Nuthall plays a record 22nd match for Wales Under-21 on Sunday and Davey praised the youngster who last month signed with the Cardiff Blues.
"He's been a good servant for Wales and Sunday will be a special day for him," he said. "He's been playing well and getting a few tries in this tournament."