The 210 had succeeded the similar 110 series, which had been on sale since two years earlier. The Datsun 114 was introduced in October 1957 as a low cost option to the 210, mainly intended for taxi use. The 114 used the 210's body except for the grille and exterior trim, combined with the old 25 PS "D10" engine to stay beneath the 910 cc limit imposed by the government on small taxis. Nissan did consider manufacturing a 908 cc version of the new C engine but in the end chose to keep the old sidevalve unit in production instead. The 114 was succeeded by the Datsun 115, a corresponding lower specification version of the updated 211, which was similar to the 114 with the exception of a bigger rear window and slightly redesigned front turn signals. The same engine was used, but thanks to some improvements it now produced and it was called the "B-1" engine instead due to its new overhead valve architecture. Small engine displacements also helped to keep the vehicle affordable, as the Japanese Government began to impose an annual road tax to help develop and maintain a national transportation infrastructure in 1950.