The Potters beat Crawley in the fifth round of the FA Cup last weekend but travel to Spain currently 1-0 down on aggregate after a first-leg loss at the Britannia.
However, Republic of Ireland international Walters, who scored the opener in his side's comfortable 2-0 win at Broadfield Stadium, feels that result could help Tony Pulis' men kick on.
He said: "It was the quarter-final victory over West Ham that turned things round for us last season when we had been through a difficult spell, and look what happened then.
"Hopefully, this win will have the same effect on our season now by getting us going in the league again and maybe even causing a shock out in Valencia.
“We know it’s a tall order and the odds are stacked against us, but we’re not out of it yet by any means, so we’ll go over there and give it our best shot.
“Valencia showed here last week what a quality side they are, so it’s going to be extremely difficult to get a result out there, but we’ll see what we can do."The cup win has given everyone a lift. A win is a win at the end of the day whatever the circumstances and that gives you confidence."
The 28-year-old was also pleased that the Potters managed to earn a clean sheet against their lower-league opponents and hopes to take that form into their Premier League games.
He added: “One of the pleasing things about it was that we kept a clean sheet and I thought we defended very well, especially with one or two lads coming into the side.“That sets us up nicely for the tough games which we’ve got coming and obviously it is very important that we get back on track in the league.”