Ford Duratec (badge, not an engine)

Duratec is a badge, not an engine. Ford has used it since 1993 for almost any petrol engine it sells, and this catalogue's own rows show it spanning 1.2 to 3.7 litres across Ford, Mazda, Jaguar, Lincoln and Mercury.

Three genuinely unrelated designs wear it here. The four-cylinders are Mazda's L-series — a joint design, and the Mazda service literature is often the better source. The V6s are Ford's Cyclone. And the Jaguar AJ25 and AJ30 are a different V6 family again, badged Duratec in the X-Type.

So a Duratec is not a thing you can look up. Establish the displacement and the internal family — L8-DE, Cyclone, AJ25 — and every useful answer follows from that.

The badge does say one thing reliably: naturally aspirated. Ford's turbocharged petrols are EcoBoost and its diesels are Duratorq, so a car described as Duratec has neither — which is a real, if narrow, piece of information.

And the four-cylinders share one characteristic worth knowing: they are non-interference in most versions, so a broken timing belt or chain does not usually bend valves — the opposite of most of what is written about timing failures elsewhere in this catalogue.