289 casting location
- Thread starter gub
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Pwraddr
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The 289 block employed a five-bolt bellhousing bolt pattern from 1963-64 model years only,
numbered C3OE, C3AE, C4OE, C4AE and C4DE. Beginning in the 1965 model year, the 289 had a
six-bolt bellhousing bolt pattern. Six-bolt blocks were numbered beginning C5AE and C6AE. The
289 High Performance block (1963-67) was the same as the 289-2V and 289-4V block with the
exception being wider, heavier main bearing caps. There was no difference in the block whatsoever.
The 302 blocks appeared for the first time late in the 1967 model year as 289 engines with casting
numbers beginning C8AE and C8OE, sporting a “302” in the valley area. It is not uncommon to find
a 302 block that was cast and assembled during the summer of 1967 as a 289ci engine. Though
302 blocks looked virtually identical to the 289 block, the cylinder bores had extended skirts to
handle the 302’s .019-inch longer stroke. This extended cylinder skirt reduced piston slap and
improved stability for quieter operation. The 302 block evolved to a certain degree in the years
following 1968. While most of these blocks are interchangeable with 289 derivatives dating back to
the 1965 model year, it is important to note that the clutch equalizer pivot boss was deleted from
the left-hand side of the block beginning with the 1975 model year.
numbered C3OE, C3AE, C4OE, C4AE and C4DE. Beginning in the 1965 model year, the 289 had a
six-bolt bellhousing bolt pattern. Six-bolt blocks were numbered beginning C5AE and C6AE. The
289 High Performance block (1963-67) was the same as the 289-2V and 289-4V block with the
exception being wider, heavier main bearing caps. There was no difference in the block whatsoever.
The 302 blocks appeared for the first time late in the 1967 model year as 289 engines with casting
numbers beginning C8AE and C8OE, sporting a “302” in the valley area. It is not uncommon to find
a 302 block that was cast and assembled during the summer of 1967 as a 289ci engine. Though
302 blocks looked virtually identical to the 289 block, the cylinder bores had extended skirts to
handle the 302’s .019-inch longer stroke. This extended cylinder skirt reduced piston slap and
improved stability for quieter operation. The 302 block evolved to a certain degree in the years
following 1968. While most of these blocks are interchangeable with 289 derivatives dating back to
the 1965 model year, it is important to note that the clutch equalizer pivot boss was deleted from
the left-hand side of the block beginning with the 1975 model year.