Mopar Distributor Identification by Shaft Length
Filed under Mopar Engine

Measured from mounting surface to end of distributor shaft.

Mopar LA engine – 3 7/8″

Mopar B engine – 3.5″

Mopar RB engine – 4″

Chrysler 331/354 Hemi – 4.25″

Chrysler 392 Hemi – 4.5″

Dodge 241/260/270 Hemi – 3 7/8″

Dodge 315/325 Hemi – 4.25″

Desoto 276/291 Hemi – 4.00″

Take care when swapping distributors as the rotation is not always the same. That information will be added as it becomes available.

http://www.hotrodreference.com/1310/mopar-distributor-identification-by-shaft-length/