The E46 M3 GTR was an exception to that rule. See, BMW made a mighty V8 to compete in ALMS GT series racing. But to qualify for the class BMW wanted to race in, a street-legal variant needed to exist.

with the latter also getting a V-8 for the rare street-legal M3 GTR. The E90/E92/E93 was the only series-production M3 with a big ol' V-8 before the F80 went back to an inline-six, which the ...