Hyundai G4C (Orion-derived, 1.5 and 1.6)

Hyundai's early petrol fours — G4CR, G4CL and G4DJ — in the first three Elantras.

These are Mitsubishi Orion engines built under licence, which the catalogue rows say out loud and which is the single most useful fact about them: Mitsubishi's 4G1 material describes the same engine, and it is far more plentiful than anything filed under the Hyundai code.

They predate Hyundai's own engine design programme. The Alpha and Beta families that followed are Hyundai's own work and share nothing with these — so a habit that holds on a Beta does not transfer backwards.

They are belt-driven on cars now thirty years old, and the belt is the item that decides whether one is worth repairing.

Parts supply is the real constraint rather than any fault of the design: the Orion is a durable engine and the cars around it have mostly been scrapped.