Zamyad M24

The 2.4 in the Padra Plus and the double-cab Karun, and the only engine this marque has ever fitted that a scan tool can talk to — Euro 5 with EOBD, where the Z24 it replaced in the same chassis has no engine management at all before 2006 and no emissions diagnostics after it.

Multipoint injection, eight valves, a compression ratio of 8.3 to 1 and 94 hp at 4,500 with 187 Nm at 2,500, from Zamyad's own datasheet. A bi-fuel version is offered and the maker publishes a real derate for it — 80 hp and 160 Nm on gas — which is worth knowing because most Iranian bi-fuel listings simply reprint the petrol figure.

⚑ What no source states is its relationship to the Z24. Both are 2,389 cc eight-valve petrol fours in the same chassis, built in the same factory, a few horsepower apart; whether the M24 is a development of the Nissan design or a separate engine is not something any source reached from here answers, and nothing published says whether parts interchange. Treat the shared displacement as a coincidence to be checked rather than as a lineage, and read the engine number rather than the badge.

The low compression ratio is the tell that it is designed for indifferent fuel, which is also why the gas variant is untroubled by it.