Austin, aka BMC, were so besotted about the torque / gallon ratio of the A series, that they were loth to fit anything other than their "All talk, no go" cams, which, although they had stood them in good stead in the post war horsepower taxation system and the mid 50s Suez oil crisis, were dier by the millennium.
Simply fitting the part number 948 cam from the 997 Cooper in a bog standard 848 Mini, made it go the way you felt a Mini ought to go. It did use more fuel, but you got there quicker.