The 3.0L Duratec V6 was introduced in 1996 to replace the aging 3.8L V6 in the Ford Taurus and Mercury Sable. Unlike its conventional pushrod predecessor, the 3.0L V6 has dual overhead cams, four valves per cylinder and an aluminum block with cast-iron cylinder liners.

It is essentially a larger version of the 2.5L Duratec 60° V6 that was introduced in the 1994 Ford Contour and Jaguar X-Type. Both engines have the same 79.5 mm stroke crankshaft, but the 3.0L engine has larger cylinder bores (89 mm versus 82.4 mm in the 2.5L Duratec).

The 3.0L Duratec engine has Sequential Multiport Fuel Injection (SFI), and an upper and lower intake manifold with electronically controlled Intake Manifold Runner Control (IMRC) that varies intake air velocity for improved low-end torque, and a single coil distributorless ignition system (DIS) that fires two spark plugs simultaneously (waster spark).

The coil is mounted on the front valve cover, and the firing order is 1-4-2-5-3-6. The plugs are gapped at 1.3-1.4 mm (0.052-0.56”).

The dual overhead cams on the Duratec engine are chain driven, so there’s no timing belt to replace.
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