The other main difference between the BT24 and the BT26 was a more powerful Repco 860 series engine, but it was also less reliable; the 1968 season was plagued by a string of retirements and Jochen Rindt left to join Lotus.

1969 saw an improvement; new recruit Jacky Ickx scored two wins and finished runner-up in the Driver's World Championship, and Brabham-Ford in the same position in the Constructor's Championship, with assistance from Piers Courage in a third car entered by Frank Williams' racing team.

With the Brabham team switching to the new BT33 in 1970, the BT26As were campaigned sporadically by privateer entries, with Peter de Klerk recording the best result, 11th (and last) at the South African Grand Prix.

In 1970 Derek Bell competed in the Tasman Series using a BT26A fitted with a Cosworth DFW, a 2.5 litre version of the DFV.

Bell's best result was 2nd in the New Zealand Grand Prix, but engine troubles forced the cancellation of the Australian leg of the series.