Steven Fletcher and Andre Bikey both scored their first goals at Turf Moor as Burnley made Barclays Premier League history.
The Clarets became the first club to win their opening four home games since promotion as they extended their winning streak on their own patch to TEN matches.
Manager Owen Coyle had said that another three points would cap a fabulous start to the season going into the latest international break and his players duly delivered to move into the top half of the table.
And once again it was another sparkling second-half showing that did the trick as Birmingham went the way of Sunderland, Everton and Manchester United.
After coming up together last season, there was little to separate the two sides in a scrappy first half but Burnley's goalpower came good after the break as leading scorer Fletcher opened his Barclays account to go to four for the season.
And a stunning goal from Bikey, who fully justified Coyle's decision to play the Cameroon international in midfield, then rounded off another near perfect afternoon for the Clarets as they warmed up for the derby clash at Blackburn Rovers in style.
Andre Bikey makes it 2-0 and another three points ...
Coyle had brought back captain Steven Caldwell for his first start of the season after the defender proved his fitness with a mid-week appearance for the reserves but sprung something of a shock by pushing Bikey forward into a holding midfield role as Joey Gudjonsson made way.
From his more advanced position Bikey crashed an early shot against a Birmingham defender, while Fletcher also saw a shot deflected wide in an up-tempo start.
But with a gusting wind making life difficult and Birmingham quick to get men behind the ball, Burnley found it hard to maintain the momentum in a scrappy first half in which neither side made a clear-cut chance unitl the 35th-minute.
Even then David Nugent could not have done much more with a well struck shot from just outside the penalty area following a thrusting run from the influential Wade Elliott which forced Joe Hart to dive to his right to save.
With Caldwell and Clarke Carlisle re-united in the back four, and Tyrone Mears and Stephen Jordan again looking comfortable in the full-back roles, Burnley had defended well to limit the visitors to even less of a threat.
But the Clarets switched off when Birmingham won a corner six minutes before the break which almost proved costly.
Burnley had every player in their own penalty area and even though an inital short corner was repelled, a totally unmarked Roger Johnson was able to fire the ball across the face of goal where Lee Bowyer had the space but not the touch to convert from close-range.
Blues boss Alex McLeish then made a double change at half-time as he sent on Liam Ridgewell and Seb Larsson and Larsson had an early shooting chance which he put wide of Brian Jensen's left-hand post.
But Burnley went ahead in the 53rd minute when they launched a rapid counter-attack through Mears after a Birmingham free-kick had been charged down on the edge of the Clarets' penalty area.
Mears had options to either side but went with Fletcher and with Blues short-handed at the back, Fletcher drove on and beat Hart with a low shot which went in via the keeper's legs.
Steven Fletcher opens the scoring with his first league goal
The goal lifted Turf Moor and five minutes later Fletcher was inches away from doubling the lead. Burnley's best move of the game ended with Robbie Blake floating a lovely pass into Fletcher, who had got behind the Blues defence and after chesting the ball down rolled a shot past Hart but agonisingly against a post.
Suddenly Fletcher was everywhere and a shot on the turn was saved by Hart before Burnley pressed home their growing superiority with a magnificent second goal with Bikey the unlikely scorer with 62 minutes gone.
Showing great strength initially to hold off a challenge from Barry Ferguson, Bikey surged forward in swash-buckling style and after playing a one-two with Nugent swept a shot past Hart before celebrating with a flying, backwards somersault.
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Burnley were now rampant and could easily have won more emphatically. With Blues having to commit more men forward another break-away ended with Nugent being tripped on the edge of the box by Stephen Carr and from the free-kick Mears forced Hart to make a finger-tip save.
Blake took the resulting corner and Bikey, who had waited almost a year for a goal, should have added to his earlier strike but from six yards out he powered his header over the bar.
A clean sheet would have been the icing on the cake and although a fabulous free-kick from Larsson with virtually the last kick of the game denied Jensen that pleasure, this was still another job well done for the Clarets as they cotinued their superb start to the season.
Burnley: Jensen, Alexander, Carlisle, Caldwell, Fletcher (Eagles 72), Elliott, Mears, Blake (Kalvenes 90), Bikey, Nugent (Thompson 87), Jordan. Substitutes: Penny, Duff, McDonald, Gudjonsson.
Birmingham: Hart, Carr, Bowyer, O'Connor, Ferguson, Johnson, Dann, McFadden, Fahey (Larsson ht), Queudrue (Ridgewell ht), Tainio (Phillips 67). Substitutes: Maik Taylor, Phillips, McSheffrey, O'Shea, Carsley.
Referee: K Friend