<VV> 63 & 64 powertrain interchangeability (long)

[NicolCS@aol.com]

Good to ask first, Dan!  Several people have already posted replies, I 
thought I'd try and throw my two cents in and either clarify or muddle things...

63 and 64 trans are basically interchangeable though you have use different 
input shafts and input shaft seals

63 and 64 standard differentials:  64 cars require either a 64-only 
differential (leaf spring) or installation of 63 rear springs and elimination of the 
transverse leaf spring.

63 and 64 transmission support crossmembers (trans to rear subframe) are 
interchangeable

63 and 64 bellhousings are different: they have to match the motor.  The 
crankshaft hub seal was relocated for the '64 164 CID engine. You must have the 
correct bellhousing for the motor

63 and 64 clutch pressure plate and flywheel systems are different (flat 
finger/flat flywheel up to '63 and bent finger/stepped flywheel for '64-up.  If 
you use the entire system (pp, flywheel, throwout, pivot ball), it can be used 
in the '64 and vice versa.

Comments about the '63 / '64 trans.  Chevy made incremental improvements in 
the trans to improve shift quality in '61 and '62 and a modest redesign in '64 
to further improve shift quality and torque capacity.  (I wrote a tech article 
about this that was in the Oct.'04 Communique)  In '64, Chevy also changed to 
a "closer ratio" gear set in '64.  Any one of the 61-5 transmissions will 
work reasonably well, but the newer the trans, the better chances you have of 
getting one with a good quality 1-2 shift.  If you go with the '63 trans (ID: 
look for a lube drain plug on the bottom rear and 12 spline input shaft) I'd 
suggest that a 3.27 or 3.08 ratio differential would take advantage of the lower 
first gear while providing a quieter and more economical highway cruise. (See 
April '03 Communique)

My daily driver is a '67 with a '61 wide ratio trans, 3.08 gears, and a 
special "hi-torque" PG 140.  It's a very sweet combo and the trans has held up well 
for years.  The only negative is that since this trans has none of the 
synchronizer improvements, I get occasional gear clash on rapid 1-2 shifts.
Craig Nicol
67 140 with 61 trans/3.08
66 140 EFI with 65 FC trans/3.08
65 140 with 61 trans/3.27

<snip>
What I wanted to do was mate a '63 tranny to a '64
standard diff, because the '64 diff I have is for a
PG.  After more inspection, I could tell a PG diff
would not work (no clutch bearing shaft, no clutch
fork ball, etc).  With all the great help from the
community, I think I can use the '63 4 spd (with the
'63 crossmember, input shaft, and input shaft seal),
'63 bellhousing , with the '64 std diff. 

I'll keep ya'll updated, I'm sure I'm not the first
one to ask this question.

-- Dan<unsnip>