The Penrith driver and Australian team-mate Jordan Love triumphed in the Silver Cup class at Misano.
It became part of round 2 of the Fanatec GT World Challenge Europe Sprint Cup.
Bird and Love, racing for the German-based Haupt Racing Team in the Paul Bird Motorsport and Hager-backed Mercedes-AMG GT3, were 3rd fastest in complimentary practice prior to declaring 2nd in pre-qualifying and after that declaring pole from certifying.
In the hour-long opening race last Saturday, Love made a strong start prior to Bird took control of for the 2nd half-hour and brought the car home in initially.
Sunday’s race, in even hotter conditions as seriously heats struck continental Europe, saw the duo surface simply except another podium surface in 4th.
Bird said: “Saturday was a mega day with pole and win in the Silver Cup class proving we had good speed overall likewise.
“[Sunday] was not the best day as we seemed to lose some performance, so qualifying wasn’t fully maximised which put us slightly further back than planned on the grid.
“The race was tricky but we just didn’t have the overall speed and we combated till completion to complete P4.
“Not the smoothest day but Saturday made up for it”.