Application: Ford vehicles with Windsor/Cleveland 351 (5.8L) cubic inch engines.

Problem: Interchanging or installing parts for the wrong engine.

Cause: Lack of information on Ford 351 engine differences.

Engine Differences:
The most obvious external difference is the engine valve covers. The 351W (Windsor) valve covers are attached with 6 bolts, straight front to rear, and narrow in width (similar to the 302 c.i. engine.)∗

The 351C (Cleveland) valve covers are attached with 8 bolts, flat
with 2 different planes, and wider in width.

The 351W engine has a radiator hose that attaches to the intake manifold, while the 351C attaches to the engine block. (See Graphic 1). The 351W takes a 5/8” thread spark plug and the 351C takes a 14mm thread plug. (See Graphic 2).

Distributor differences:
The 351W has a smaller 1.245” diameter distributor gear, and the 351C has a larger 1.418” diameter distributor gear.

Each engine has a 5/16” oil drive at the bottom of the shaft and a 1.557” diameter housing, measuring directly above or below the O-ring area.

Note: &lowa...