Thread: Difference in V6 blocks
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Old September 13th, 2022, 06:23 AM
Prowbar Prowbar is offline
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Default Re: Difference in V6 blocks
305, 351 and 379 all use the timing chain. 401, 432 and 478 do not as they use a gear style camshaft drive. This means there is a difference in the main oil galley to supply oil to the middle idler gear. However, a 478 or 401 is easily modified to take a timing chain.

Also my 478 has extra oil drains for accessories and governor oil connections. Bellhousing bolt patterns are the same as are the front cover bolt patterns and motor mount connections. Main and rod bearings throughout the range are the same except for the 73-74 478 which have larger mains. Pete Chronis told me this.
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