A 2-1 win over Southampton at St Mary's on 2 March was followed up by a 3-1 home victory against Sunderland last time out.
Three points from the trip to the West Midlands would take the Rs to within a point of Villa in the table and Redknapp recognises how important it is to both sides.
"It's a big game - a massive one for both teams," he said.
"It's not make or break but it's massive to how the table will look on Sunday morning. We need a result.
"We were given no hope and the pressure isn't on us so much.
"All along, I've said we can survive. These two wins (Southampton and Sunderland) have given us confidence.
"We're in good form - just two defeats in the last nine games."
Redknapp has confirmed that Adel Taarabt is fit, while Julio Cesar and Armand Traore should also be available for selection.