Erich & Listers,
Just to add to the confusion, the casting numbers on my 5 bolt 260 block
(4F30) indicate it was cast on June 30, 1964, however the stamping in the
block (4L20A) indicates it was assembled on November 20, 1964.
I have interpreted the codes using "how to rebuild small block Ford engines"
by Tom Monroe.
Doug Leithauser
Date: Sat, 9 Mar 2002 21:06:08 -0800
From: "Kathy and Erich Coiner" <kathy.coiner@gte.net>
Subject: 5 bolt vs 6 bolt bell housings
Some months ago, the subject of when did Ford change over from 5 to 6 bolt
bellhousings. At that time a number of people thought the change occured in
late 1965.
I asked this question at www.fomoco.com and received two replies.
1. RE: 5 bolt vs 6 bolt bell housings
by john - 9:09:57 PM; IP 168.191.86.167
the transition date between 5 bolt and 6 bolt bellhousings as stated in the
Ford Master Parts Catolog is either 17 august or 20 august, 1964 depending
on the catalog or part of the catalog your reading from. early mustangs (so
called 64 1/2 but titled 65 mustangs) that had 5 bolts bellhousings are
coded F (260 v-8) or D (289 4-v regular fuel). these are considered 1964
engines. C-code and A-code engines are 6 bolt and considered 1965 engines.
the 289 hi-po is the same way, 5 bolts makes it a 64 and 6 bolts makes it a
65 engine. hope this straightens out your dilema.
2. In theory, the change was made by August 1, '64. [n/m]
by Mr F - 12:04:54 AM; IP 68.80.223.14
For those who want to see the source info, follow the link below.
Someone has responded to your post. Click here to see it:
http://fomoco.com/forummain/reply.asp?ID=44020&Reply=44020
So it looks like Ford changed to the 6 bolt bell housing at the beginning of
the 65 model year.
Erich
|