This unique BMW Z3 M with its M73 V12 engine is a car that makes every BMW Z3M owner growing a soft spot for.
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While it never saw production, a few BMW enthusiasts from worldwide actually have built the very same car, using the M73 or alternatively the M70 and even the S70 engine off the E31 850CSi.
Supersprint still manufactures the right headers and performance exhaust for the task, which are designed to fit like a glove and and complete this conversion to factory-like specs.