C3 Tach Drive Distributor Ident 68-74

[jim34671]

Without an ident band around the distributor housing,how can one source the origin of the unit?
Besides the hole on the case opposite the tach drive gear,is there any other clues to differentiate year and application?..ie BBC/SBC,etc??
Thx

[Craig S.]

Re: C3 Tach Drive Distributor Ident 68-74

Earlier units did not have the hole through the cast iron housing for the button that serves a wear bearing surface for the tach cross drive gear..I believe that this change came around 1970 or so. Also, on the maishaft and rotating cam assembly or pole piece if mag trigger you should see a 3 digit number stamped on a surface, usually on the bottom side if you peer up at the base. The autocam frequently, but not always, has a two digit number stamped as well, sometimes on the top under a spring, and sometimes on the bottom underside. Again, this is an ID of the autocam. There are charts that list these ident numbers and applications, and this can serve to ID the unit. I don't have these charts, but I have worked through Dave Fiedler to ID based on this. He usually works mainly with TI distributors, but, has helped on occasion with ID of other parts. I do remember the Alan Colvin by the numbers books have a pretty good section on distributors, they may have these details...Craig