Originally Posted by Dave1234
What are main and rod bearing journal diameters?

248, 270, and 302 all run the same rod and main bearings, and journal diameters:

Connecting rods: Federal-Mogul #1905CP Standard diameter 2.3110-2.3120

Main bearing set #679M- - - -1954-55 engines
bearing #1: F-M #9846CP std. shaft diameter 2.6835-2.6845
bearing #2: F-M #9847CP std. shaft diameter 2.7145-2.7155
beating #3: F-M #9848CP std. shaft diameter 2.7455-2.7465 ( Flanged thrust bearing)
bearing#4: F-M #1909CP std. shaft diameter 2.7765-2.7775

Main bearing set #4030M- - - - -1956-63 engines

Same crankshaft dimensions as above.

#3 main bearing is F-M #1908CP No difference in the other bearings or dimensions.

Information from Federal-Mogul shop specifications book #115- - - -1982 edition.
Jerry

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