Engine Swap -- 1959 for a 1955

[Mike Josephic CLC #3877]

As many of you know I am the "Technical Advisor" for
1955 & 1973.  A member called me with a question
today that I am unable to answer.

He recently bought a 1955 CDV that has a bad engine.
He can get "cheap" a complete engine & tranny from
a 1959.

His question is -- is this a feasible swap that can be done
without major modification?  He's hoping for a "drop in"
or close to it.

The fellow's name is:Bob Hirschberg, Member #24597.
He's not computer literate, so he could not post a message
here.  If anyone knows for sure, either post it here and I'll
phone him.  Or better yet -- if you can explain to him what's
involved call him directly at 845-247-7555.

If you've contacted him please let me know.

Mike

[Bobby B]

Mike,
Why not just rebuild what's in there, especially if it's the original engine?
                                                              Bobby

[Mike Josephic CLC #3877]

The engine in the car is not original -- it's out of a '54.
Also, he doesn't want to spend the money on rebuilding
it.  It will run (barely) but has a loud "knock".  It sat
for 15 years like that.

Mike

[Roger Zimmermann]

Mike, I'm just thinking at the obvious. Engine supports 54-56 are not the same as 57-62, but it may not be a problem. The transmission for the 59 models is shorter (but I don't know if he can get engine and transmission) and may requires a different rear support and drive shaft. If he is getting the engine alone, the 55 transmission will not go on the 59 engine without heavy surgery.

[55hooptie]

My 1955 has a 1958 engine in it and I know the exhaust manifolds ports are different and had to use 2 right side center dump manifolds. My front pulley is extremely close to the cross member which may be from old worn out engine mounts. If I remember right, 58 is a 365 and 59 started the 390. Not sure if the blocks are the same.

[J. Gomez]

As many of you know I am the "Technical Advisor" for
1955 & 1973.  A member called me with a question
today that I am unable to answer.

He recently bought a 1955 CDV that has a bad engine.
He can get "cheap" a complete engine & tranny from
a 1959.

His question is -- is this a feasible swap that can be done
without major modification?  He's hoping for a "drop in"
or close to it.

The fellow's name is:Bob Hirschberg, Member #24597.
He's not computer literate, so he could not post a message
here.  If anyone knows for sure, either post it here and I'll
phone him.  Or better yet -- if you can explain to him what's
involved call him directly at 845-247-7555.

If you've contacted him please let me know.

Mike

Mike,

Not sure if you, him or someone on his behalf also posted the same at the MCLC forum -> https://www.modifiedcadillac.org/forum/index.php/topic,9460.0.html

I do not believe it would be an easier or simpler swap between them. There are several variances which would require major modification to transplant a 390 to a 331 frame.

The mounts both motor and transmission are different between them, the crank pulley is about ½” bigger for the 390 which I believe the front brace angle is deeper on the ’59.

Outside from other ancillary pieces been different the drive shaft would require some modification.

If you (he) can pull the AMA specs for both years from the GM heritage center these could give you a high level details between them, although not much detail there but at least something to go by.

Good luck..!   

[Caddy Wizard]

If the guy is not in a hurry, he should bide his time and wait for a good running 55 engine to come up for sale.  They do quite regularly, as some folks opt to put in a Chevy 350 or an LS motor.  That would be the simplest and cheapest option by far.

[Mike Josephic CLC #3877]

Jose:

Bob called me today and told me you spoke to him
Thanks for helping him out.  Based on what you told
him, he's decided to stick with what he has, which
I think is the wise approach.

Mike

[J. Gomez]

Jose:

Bob called me today and told me you spoke to him
Thanks for helping him out.  Based on what you told
him, he's decided to stick with what he has, which
I think is the wise approach.

Mike

Mike,

Sure no problem.

Yes he called my land line and was a bit surprise (from his message ) if it was a working line since I have a special vmail recording for telemarketers.   

Bob mention he has a ’54 engine and transmission and was worry about a knocking sound he thought was a piston rod while test driving which he needed to checkout.

I agree with you, time and $$$ is better to stick with the simpler approach.

[35-709]

Maybe if he is real lucky, it will be a carbon knock that a can of Seafoam down the carburetor will cure.  Very nice of you to call him Jose.

[J. Gomez]

Maybe if he is real lucky, it will be a carbon knock that a can of Seafoam down the carburetor will cure.  Very nice of you to call him Jose.

Geoff,

Is it part of our Cadillac community for us to help and pass information to other Cadillac owners.   

[35-709]

Indeed!   

For what it is worth, I have known Bob Hirschberg for several years, unfortunately I couldn't answer his question either.