Installing a 55 motor in a 38 car with standard transmission

[robert G. smits]

How difficult is it to mate a 55 motor to a 38 standard transmission?  I have been told that 53 is the last year that they will match up.  There must be an old thread on this somewhere but I can't find one.  Any information would be appreciated.  Thanks, Bob Smits  #2426

[Steve Passmore]

I can't help you there Robert. Never tried it, but I feel if it was as easy as that we would have seen a lot more pre war Cadillacs with 50s engines fitted and I can't say I have!  Anyone else???

[robert G. smits]

When I was a senior in high school I put a floor shift Cad transmission behind a 57 Olds J2 and dropped it in my 53 Ninety Eight hard top.  Very satisfying ride, wish I would have kept it.  The reason for my question is that I have the 38 with a cracked block and a low milage 55 motor is available  I have been unavailable to find a rebuilt flathead for some time although finding a flathead to rebuild may end up being the simple solution

[35-709]

Perhaps contacting one of the engine/transmission adapter companies will get you the help you need.  Two of the big dogs ---

Bendtsen's --- http://www.transmissionadapters.com/

Wilcap --- http://www.wilcap.com/webdoc8.html

There are others to be found with a Google search

[Jay Friedman]

A 55 motor cannot be mated to a standard transmission because in that model year Cadillac changed the back of the engine in a way that a standard transmission could no longer be used with it.  (If you want to know the details email me at jaysfriedman@yahoo.com.) 

FYI: Oldsmobiles could still be equipped with a standard transmission in both 57 and 53.  In fact, 50 Oldsmobiles with a standard transmission used a Cadillac type transmission so, as you must know, a floor shift Cad transmission will bolt right up to a 1950s Olds engine if a 50 Olds stick bell housing is used.

While 53 was the last year Cadillacs could be equipped with a standard transmission (Hydramatic was standard equipment from 54), in fact a 54 motor could be mated to a standard transmission and Cadillac still supplied replacement engines for pre-54 cars with stick shift.  This was no longer true from 1955.

I have heard of a 55 Cad motor used in a race car with a manual transmission, but to do so the sponsors of the race team spent lots of money to fabricate a special bell housing and adapter.  I think a better solution is that you try to find a 49-54 Cad motor for your 38 since they will bolt right up to your 38 transmission if you use a 49-53 stick bell housing.  Nonetheless, the best solution is that you find a re-buildable flathead since you may have to do quite a bit of adapting to install the 49-54 motor in your 38.  (You may want to contact CLC member Brad Ipsen who installed a 50 or 51 motor in a 40 LaSalle.)  Or, maybe again, one of the firms 35-709 suggests may help.

[robert G. smits]

Thank you to everyone who replied.  The knowledge of participants on this forum never ceases to amaze me.  When I heard about the low milage 55 motor with all the accessories it sounded like a great solution.  The 38 has been sitting in my cc garage for 30 years because I have always had other projects.  I think I will concentrate on finding and rebuilding a 41-48 flathead.
Bob Smits #2426

[goofyhb]

I would be interested to put the 55 motor into my 55. Than I could still cruise around while rebuilding my original engine.