Martyn Thomas returns to his usual full back berth after a run out on the wing at Saracens last weekend, Shane Monahan takes over at left wing and Dan Robson replaces Jimmy Cowan at scrum half.
Davies has also unveiled a slight twist to his fly half/ inside centre axis, with Tim Taylor wearing ten and Freddie Burns twelve, therefore giving two possibilities at first receiver and left and right foot kicking options.
There is a new look, but experienced front row, in Nick Wood, Huia Edmonds and Shaun Knight while Tom Savage partners Jim Hamilton in the second row.
Sione Kalamafoni moves back to the flank after appearing at number eight last weekend, with Matt Cox and Gareth Evans completing the back row.
Irish currently lead the pool with ten points, just ahead of Gloucester on nine points, so there is a lot at stake.
Gloucester have already won once at the Madejski this season but Davies doesn't think that will have too much bearing on Saturday's game.
"That was only the second week of the season and we were all just finding our feet, so I don't think you can read too much into that game.
"It'll be interesting to see how they approach this game. Obviously they've got a lot to do in the league, and we still have big ambitions in the league ourselves.
"We're going to go pretty full on, as we do for every competition. We will change things up a little bit and give opportunities, but it's a strong team.
"They've done very well in their two games so far in this competition, and there's no doubt that the next two games will very much determine how the pool shapes up."
Martyn Thomas; Charlie Sharples, Tim Molenaar, Freddie Burns, Shane Monahan; Tim Taylor, Dan Robson; Nick Wood, Huia Edmonds, Shaun Knight; Tom Savage, Jim Hamilton (capt); Sione Kalamafoni, Matt Cox, Gareth Evans
Darren Dawidiuk, Dan Murphy, Rupert Harden, Will James, Ben Morgan, Dave Lewis, Mike Tindall, Rob Cook