The 6-cylinder units shared the same 120mm cylinder stroke length, but the bore (cylinder diameter) on the larger engine was increased by 5mm to 80mm. Although a new more modern Vivastella was introduced for 1934, the earlier model continued to be listed, at an attractively lower price, in the catalogue.
The 6-cylinder engines shared the same stroke length (120mm), but the larger engine had a larger bore (80mm) compared to the smaller one. A newer Vivastella was introduced for 1934, while the older model remained available at a lower price in the catalog.