The Carrickfergus man is one of eight riders who will battle it out for the title over the next three rounds, with the championship finale taking place at Brands Hatch next month.
Irwin is currently in seventh place in the standings, only 14 points behind Christian Iddon in third.
A winner for the first time this season at Silverstone a fortnight ago, the 31-year-old has an outside shot at the title, with McAMS Yamaha riders Jason O’Halloran and Tarran Mackenzie leading the way after a dominant season for the R1.
“The first part of the season has been a success despite some difficulties from a technical point of view and also with my shoulder injury,” Irwin told the News Letter.
“To achieve that together with my team, I think we have to be happy but it’s also what I expect from myself.
“That part is done and dusted and we’ve had a weekend off, when I went to the Ulster Superbike round at Bishopscourt to chill out and relax before these final three rounds.
“We’re in with a fighting chance and we have three tracks coming up now, which are very different. One is really strong for the bike, there’s one where we need to put a lot of work in and then Oulton Park is somewhere in between,” Irwin added.
“I think if I get the potential out of myself and the bike in every race, then we might do ourselves a lot of good in trying to finish in that top three or top five in the championship.”
Irwin is also maintaining a positive outlook over his title prospects, with the Ulster rider stressing that anything is possible with nine races still to go in 2021.
“Looking further into that, yes it’s mathematically possible to win the title and we saw last time out that anything can happen,” he said.
“I’m not going into the weekend thinking that we can’t win the championship because we saw what happened with Jason and Tarran [at Silverstone], and I know how they ride with each other! I expect more fireworks to come and all I can do is give it my best shot.
“We have a bike that can win races and we can’t win everywhere at the moment, but if we can get the most out of it at some of these other circuits and try and win when we can, then we can be in a good position, I think.”
Race one on Saturday is at 4.30pm with Sunday’s BSB race scheduled for 1.10pm and 4.15pm.