The 351 Cleveland, on the other hand, belongs to Ford's 335 engine family. This thin-wall cast BIG SMALL BLOCK uses the smaller 14mm spark plugs, has a separate front cover (bolted to the block) housing the timing chain and routing water - so that water does not go through the intake manifold, features beefy main caps (wide enough to drill for 4-bolt mains), a poor oiling system, and uses different heads for 2V & 4V versions. The heads make all the difference and these fire breathing babies make this motor the legend it is. On the 4V, the valves are HUGE, measuring 2.19" intake and 1.7n" exhaust (don't remember exactly). Valves this large are only possible via a canted valve arrangement, forming what Ford refers to as a "poly-angle" combustion chamber. The valve covers are not straight - the front is flat and parallel to the ground, but a curve twists the rear parallel to the head. They are attached by 8-bolts and when removed, there is a 4 cast into the corner of the 4V and a 2 cast into the corner of the 2V (at least in 1970). The canted valves are the dead giveaway.
|351 Windsor||351 Cleveland|
|5-bolt straight valve covers||8 bolt 2-plane valve covers|
|radiator hose to the intake manifold||radiator hose does not connect to intake|
|regular 5/8" spark plugs||small 14mm spark plugs|