351W (WINDSOR) VS 351 (CLEVELAND)
The Windsor engine plant builds this engine; hence the name. Normally, this isn’t important. But another engine, the 351C (for Cleveland engine plant), has the same displacement. That’s about all they have in common. So, it’s always important to differentiate between the two. The 351W is a beefier block than the 289/302, but has the same bore spacing (4.38") and bore diameter (4.00"), so heads retrofit. A higher deck height requires a unique intake manifold. Main journals (3.00") are larger than the 289/302 (2.25"). Camshafts interchange, but the 351W has a different firing order: (1-3-7-2-6-5-4-8) vs. (1-5-4-2-6-3-7-8) for the 289/302, except 1982 and later 302 HO which use the 351W firing order. The 351W has been used from 1969 to the current year.They are both 90 degree V's.In fact, the Windsor was originally named the '90 deg V small block'.Clevelands are wider because they have a taller deck height.9.213" as opposed to 8.206".
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