 The prototype appeared in the first quarter of 1954, powered by an inline four with overhead camshaft (driven by chain) and cross-flow hemi head.Since the OHV engine was not ready in time, production M21s had a sidevalve four, based on the GAZ-20's.The Volga was offered with a three-speed transmission, either manual (with synchronized 2nd and 3rd gear) or automatic.