Towering second row James Sandford has been ruled out due to injury and his place has been taken by David Nolan, who moves up from the replacements bench. Local Buccaneers boy Trevor Conneely will take the vacancy on the bench left by Nolan.
In the back-line, Conor Cleary moves from the replacements to start the game at inside centre, with Eamonn Sheridan dropping to the bench.
Elwood said: "The last game started very well for us and we really hit a rhythm in all aspects of our play and Scotland were on the back foot in the first half. We were all a little bit disappointed that we did not kick on from there after the break, but as I said before the game, Scotland are a very good side and began to come back into the game in the second half.
"We dug deep and closed out the win, which was another positive aspect, but overall I was happy with how the guys responded.
"We have lost James (Sandford) to injury, but David (Nolan) is a ready-made replacement for him, so I do not see any issues in that department. With regard to the change in the centre, we thought that Conor Cleary might offer us something a little bit different for Friday night.
"This game is another jump up again in terms of the level of opposition as Wales have won two on the bounce and been impressive in beating Scotland and Italy, so I think we will need a disciplined 80-minute performance if we are to get a win on Friday night."
IRELAND UNDER-20 TEAM & REPLACEMENTS (RBS U-20 Six Nations, Friday, March 7, Dubarry Park, kick-off 7.35pm):
15 - David Kearney (Lansdowne/Leinster)
14 - Sean Scanlon (UCC/Munster)
13 - Eoin O'Malley (Old Belvedere/Leinster)
12 - Conor Cleary (Greystones/Leinster)
11 - Chris Cochrane (Queen's University/Ulster)
10 - Martin Dufficy (Dublin University/Leinster)
9 - David Moore (Blackrock College/Leinster)
1 - Paul Karayiannis (Queen's University/Ulster)
2 - Jason Harris-Wright (Greystones/Leinster)
3 - Ben Barclay (UCD/Leinster)
4 - David Nolan (Galwegians/Connacht)
5 - Eoin Sheriff (Lansdowne/Leinster)
6 - Kieran Essex (UL Bohemians/Munster)
7 - Paul Ryan (Blackrock College/Leinster) (capt)
8 - Patrick Mallon (Lansdowne/Leinster)
16 - Stephen Douglas (Ballymena/Ulster)
17 - Stephen Archer (UCC/Munster)
18 - Ian Nagle (UCC/Munster)
19 - Trevor Conneely (Buccaneers/Connacht)
20 - Ian Porter (Queen's University/Ulster)
21 - Ian Madigan (Blackrock College/Leinster)
22 - Eamonn Sheridan (Lansdowne/Leinster)
Manager - Phil Orr
Coach - Eric Elwood
Assistant Coach - Dan McFarland
Under-20 Six Nations Fixtures
Ireland U-20s v Wales U-20s, Friday, March 7, Dubarry Park, Athlone, kick-off 7.35pm (live RTE TV)
England U-20s v Ireland U-20s, Friday, March 14, Kingsholm, Gloucester, kick-off 7.45pm