The 22-year old Allwood has been named on the wing for just his second NRL appearance of the season, while Ikahihifo replaces the injured Jacob Lillyman at prop.
The one other change from the squad used in the 50-16 loss to North Queensland last Saturday is Bodene Thompson returning to the back row after making his comeback appearance from the bench last weekend.
Allwood has had an injury-plagued season - scoring in his Warriors debut against Brisbane in March before being later sidelined by an ankle injury.
Ikahihifo has played predominantly in the New South Wales Cup this year but now returns for his eighth NRL outing of the season while Thompson's inclusion ensures the experienced combination in the back row with Simon Mannering and Ryan Hoffman is fully restored.
After debuting last weekend, Mason Lino is again in the halves with Tuimoala Lolohea.
"I always smile when players like Mason make their debut. He was really calm the way he approached the game and showed lots of nice touches. You can see that he and Tui have a lot of understanding having come through the grades together," said Warriors assistant coach Andrew Webster.
Webster also believes the Warriors pack will hold up without Lillyman and the suspended Ben Matulino, and is glad to see Allwood be rewarded for his hard work in training.
"With Jake out and Ben still suspended we're missing a huge amount of experience in the front row but we know what Seb will give us and Albie [Vete] was really impressive with the way he kept pushing through and turning up against the Cowboys.
"It's pleasing to see Matt being given a chance. He has put the work in and deserves this."
For Webster and Thompson this week's clash will be a homecoming of sorts with both joining the Warriors this season from Wests Tigers.
After six losses on end Webster said the players and coaching staff were desperate to atone for the recent run of reverses.
They face a Wests Tigers side sitting last on the table on 18 points with both teams coming off heavy defeats, with the Tigers losing 40-18 to Cronulla last Saturday.
The match kicks off at 4.00pm on Sunday.
Warriors: Sam Tomkins, Matt Allwood, Dominique Peyroux, Solomone Kata, Jonathan Wright, Mason Lino, Tuimoala Lolohea, Sebastine Ikahihifo, Nathan Friend, Albert Vete, Bodene Thompson, Ryan Hoffman, Simon Mannering.
Reserves: Konrad Hurrell, Sione Lousi, Charlie Gubb, Sam Lisone, John Palavi.
