The Potteries club are considered long shots, 20-1 by one bookmaker to win in west London, but Pulis is always confident his resilient players can produce the shocks.
Pulis said: "We have got very close to taking something from Chelsea in the past couple of seasons, but still not managed to beat them. But we have a game plan, we always do against one of the big clubs, and we always believe we can achieve something in these sort of games."
Stoke can beat their points tally for last season if they do produce a positive result at Chelsea, and Pulis added: "I am delighted that we have already reached a position in the season where we are safe from relegation already.
"It is now good to be involved in such high-profile matches against Chelsea and Manchester United in our final four games, and we will be facing teams fighting for their lives. That will give us the incentive to respond."
Stoke will have defender Ryan Shawcross back in their squad for the first time since February following an ankle injury. Striker Mamady Sidibe is their only serious injury doubt with a groin problem.
Pulis continued: "We can almost touch 46 points now, it is very important that we overtake last season's tally of 45, and to maintain our position in the top half. That shows progress.
"If we can get to that mark it will be a cracking season for us, better than the last one and showing we have got better.
"I certainly wanted to get to that stage in points won, or close, before we faced the last few games at Chelsea, Manchester United and at home to Everton, as well as a visit to Fulham.
"They were always going to be tough games. Everton are a very well-organised side with their injured players back now, while going to Stamford Bridge and Old Trafford will see us facing one of the sides who will be the champions.
"If Chelsea don't do it then it will be Manchester United. That is a tough end to a season for anyone, and we are aware of the challenge.
"People probably won't give us much of a chance at Chelsea, but we will give a good account of ourselves and play to our very best."