Boss Mick McCarthy dispensed with a 4-4-2 formation earlier this season and switched to 4-5-1, using Kevin Doyle as the spearhead.
Since then Wolves have lost just five of 13 Premier League matches to leave themselves six points clear of the relegation zone with four games remaining.
"At the end of the day you can't complain if the team are doing well and getting points," Iwelumo told the club's official website.
"The 4-3-3 or 4-5-1 has worked so well and has put us into the position we are in this season.
"The whole objective of the season is to stay in the league and we've come a long way towards doing that in the last couple of months."