Nineteen seventy-three marked the first year that F2 became more important to March than F1, with the new two-litre rules heralding the beginning of a long relationship with Paul Rosche at BMW.
1973 foi o primeiro ano no que a F2 fíxose máis importante para March que a F1, as novas regras dos dous litros marcaron o comezo dunha longa relación con Paul Rosche en BMW.