The engine comes from the same lineage as the BMC-developed E-series family introduced in the 1969 Austin Maxi, but with important modifications in order to facilitate compatibility with a conventional "end-on" transmission unit, in place of BMC/BL's traditional "gearbox-in-sump" configuration for its front wheel drive vehicles.
Fuelling was by means of a single carburettor in most applications, and electronic fuel injection for the higher-specification variants of the Rover 216 producing peak power of 103 brake horsepower (77 kW).
[3] BL had also developed the earlier R-series engine from the E-series family, but largely as a stopgap at the Maestro's launch since the S series was not yet ready for production.
Because the E series had to be turned through 180 degrees in order to facilitate an end-on transmission, the resultant R-series unit had the inlet manifold on the front-facing side of the cylinder head, something which proved fatal for the engine's reliability—since it opened the door for carburettor icing.
Another important change vis-à-vis the E/R series, one with potentially negative consequences for the engine's durability, was driving the camshaft by a toothed belt in place of the previous timing chain system.