Ford 335 Engine - 351 Cleveland

351 Cleveland

See also the Cleveland-derived Boss 351 and quite different 351 "Windsor"

The 351 Cleveland was introduced in 1969 for the 1970 model year as Ford's new performance-car engine and was built through the end of the 1974 model year. It incorporated elements learned on the 385 big-block series and the Boss 302, particularly the poly-angle combustion chambers with canted valves, and thin-wall casting technology.

A 4V (4-barrel carburetor) performance version and a 2V (2-barrel carburetor) basic version were built, both with 2 valves per cylinder. The latter had a different cylinder head with smaller valves, smaller ports, and open combustion chambers to suit its intended applications.

Only the Q-code 351 "Cobra Jet" (1971–1974), R-code "Boss" 351 (1971), and R-code 351 "HO" (1972) versions have 4-bolt mains although all 335 series engines (351C/351M/400) have provision for them. The main differences between 351C/351M/400 engines are the connecting rod length, and the main bearing size. The 351M/400 engines have the larger bearing size and the taller deck height while sharing the 429/460 bell housing pattern. The 351C engine has a medium main bearing size (2.75") and shorter connecting rods (5.78") than the 351W (5.94") and the 351M/400 (6.58") while retaining the SBF (289-302w) engine mount locations and bell housing pattern. The 400 engine has the longest stroke (4.00") of any SBF or 335 series engine.

All of the 351C and 351M/400 engines differ from the 302/351W by having an integrated timing cover casting in the front of the block to which the radiator hose connects.