Pontiac Power for 58 Cadillac
 

I know someone out here can help me, even if only in theory or by hearsay...

I have a 1960 Pontiac 389 engine with a 4 speed Hydramatic that I want to put in a 1958 Caddy I recently purchased.

I believe the Caddy has a cracked block or at very least needs head gaskets. There's lots of water/antifreeze in the oil but the engine turns over OK. Hasn't been running in 10 years and there's been no carb on it for just as long. The intake holes were uncovered, just to make matters worse. On the dip stick it reads about 1/2 -1 full quart over the full line. Any chance it's just condensation build up and not the head gaskets/cracked block?

Anyway, what's the procedure to put this Poncho engine into the Caddoo?
Will the Pontiac Engine and Hydramatic swap in pretty easily?

Anybody done this before?

Wow That is a nice looking Cady. why dont you at least remove the heads and see if there is a cracked head. Also drain the oil from what you describe there is water in the oil.

I agree I'd at least give the Caddy a oil change and a AFB and see what hap pends.

That is a nice Caddy!!!! You got one hell of a nice line up there................

"all of a sudden in a wink of an eye a Cadillac Sedan passed us by"
Hot Rod Lincoln

Cracked head(s). They are well know for it.

I had a 65 389/TH400 put in a 58 Cadillac. The biggest problem is exhaust. I had headers made.

E-mail me and I'll send you my number if you'd like to talk.

Carmak
Riverside, Iowa

That one is nice on the eyes!

Gosh, IMHO if anything begged for a Caddy 500 swap.... man that's it! Just saying.

as much as i like pontiacs, i think your car would be way cooler if kept all caddy.

Caddy Newbie
 

I agree it'll be best to keep it all Caddy and didn't know they were known for cracked heads. I can live with that, just not a cracked block. There's a car show/swap meet coming up here in Charlotte. I'll be working on this engine today and will get back here with the prognosis..

Ideally, of course, I'm hoping to just flush the fluids out and all will be well but want to have plan B in the ready. A 500 would be excellent, I agree. Anybody know if the mounts are the same? Anybody know of a Caddy forum?

Man, this car is a frikken WHALE!

Here are a couple more shots.
It needs a few trim pieces but the body is beautiful!

Cadillac Forums
 

This is a big Cadillac forum. I have a link to a Co. that specializes in the older Cadillac engines I am looking for that link.

http://www.cadillacforums.com/forums/

This is another Cadillac site you might be interested in, if you are thinking about an engine swap.
http://www.mtscadparts.com/

Thanks for the links. I'll definitely check them out.

I put an AFB from a 63 GP on there just to see if she'll cough for me.
No luck on the fireup yet.

Might be points, bad coil and/or wires so I'm getting some new stuff in the next few days for it.

Thanks for your help...

Sweet Caddy indeed!

Here is another vote for keeping it Cadillac powered. Unless you would plan on doing a full resto-mod to it, it just wouldn't seem right to anything else powering it IMO.

I am also in favor of keeping everything original.....BUT....it can cost big $$$$$$$

I have attached a few pictures of my wire's 57 Coupe Deville (the 57 and 58 are the same body generation). I rebuilt the engine about 5 years ago(it's a late 58 365). These are very expensive engines to get parts for.

During this era Cadillac revised their engine annually. The heads are unique year to year (and side to side) as are the water pumps and exhaust manifolds. Mid year 58 Cadillac changed from a rope rear main to a neoprene rear main.

The hardest thing to find for these engines are heads, exhaust manifolds and intakes that are not cracked. The heads crack near the center exhaust port. At the time I could not find anyone willing to weld them due to the proximity to the exhaust port.

For my rebuild I used a pair of 60 390 heads that I found after 6+ months of looking.

I bought a 58 that had been is a ditch since 1968 and hauled it 100 miles home to get a pair of low milage exhaust manifolds. The water pumps cost $200 + core.

If I had it all to do over again I would put a 425/472/500 in it.

Carmak
Riverside, Iowa

P.S. The year after I rebuilt the engine I sold a numbers matching driver 65 2+2 for $1000 less than it cost to rebuild the 365 (and i did all of the labor).

holy chit! and we complain about the cost of pontiac stuff?

"The hardest thing to find for these engines are heads, exhaust manifolds and intakes that are not cracked. The heads crack near the center exhaust port. At the time I could not find anyone willing to weld them due to the proximity to the exhaust port.

For my rebuild I used a pair of 60 390 heads that I found after 6+ months of looking."

Any idea why the heads crack? I'm hoping this is not the case but if it is I'll either need one or both. And I guess 1958-1960 heads are interchangeable? Any other years?

Or, as I said at the beginning, I'll want to put the 1960 389 w/Hydramatic in this car. Anybody know if it's an easy drop in to one of these Cadoozellers and if the trans/motor mounting positions are the same?

To make a 389 fit in my 58 I had motor mounts welded to the frame, notched the crossmember and had headers made. Additionally I was going to need to make new mounts for the power steering and block off the fuel pump.

The engine nessels way down into the frame, the lower pulley nearly touches the frame crossmember. The upper control arms come very close to the engine. Notice how the Cadillac has all of it's accessories mounted up high.

One of the advantages of using a 472/500 is that Cadillac continued to mount the accessories high on these engines.

The bummer is that neither option (original engine or a transplant) is easy or cheep.

As for the heads it was my understanding the 58-62 heads are interchangeable in year matched sets (a pair of 59's or a pair of 61's etc...). It's possible that the 59 & 60 heads are the same and the 61 & 62 are the same. I know 57 & 58 heads are not the same and between 58 and 59 the engine grew from 365 to 390 so there is a slight chamber volume change. The heads have a poor design that is susceptible to cracking around the center exhaust port.

I guess I would pull the heads and be sure it's a cracked head. If it is then see if you can find one. If you can then go with the Cadillac, if not then look into a transplant.

Carmak
Riverside, Iowa

Progress~ Pontiac Carb on Cadillac Engine
 

OK, She finally fired up!
One step closer to keeping her all Caddy, well except for the carburetor.

At first she just spun pretty quick with not much compression and no combustion. The breather pipe was puffing like a locamotive, too. Obviously serious Blow-By.

A friend at my local post office told me about an old tractor they got running after 10 years of sitting. He said that the rings had lost their seal to the walls of the chamber and collapsed a little because the oil had receeded and there were open exhaust valves. Probably a thin layer of rust in there and a couple of sticky valves.

Applying this theory here, I had to take out the plugs, pour about an ounce of Marvel Mystery Oil into each cyclinder and put in some fresh plugs. I then put on a 3300 SA Carter AFB I had laying around, poured some gas in the carb and cranked it for a while. Finally fired up after cleaning the plugs a couple of times. Looks like it needs a fuel pump. Definately not pulling fuel up from the can. Might be why the carb is missing, probably thought that was the problem. I made a gravity feed with a funnel of gas. Now she'll run in spurts of 30-60 seconds or so.

I made a couple of YouTube videos:

http://www.youtube.com/watch?v=wjCAhnNjJ2o

http://www.youtube.com/watch?v=ftFCfkO4OSE


Anyway, still haven't determined if the heads are/head is cracked or why there was about a half quart of water in the oil before I changed it. Maybe condensation from being open up top for so long?? I'm hoping.. The good news is that there's no more in there now than there had been before I started messing around with it.

There is antifreeze, however, leaking out from under the engine. Freeze Plug maybe? I'll see today. I'm changing the oil with some cheap/thin stuff and quarter of marvel oil to let it run for a few hours then I'll change it again. Anyone have any other suggestions for conditioning this old engine? It's like waking up Rumplestillskin..

Also, anybody know about the freeze plugs on a Caddy like this?

Sound pretty good for not running for 15 years!! It sounded like there wasn't even any lifter noise. As for the freeze plugs, according to NAPA's Pro-Link they are a 1 31/64 diameter. But they are not the cup type . I posted a pic of them so you get an idea of what they are.

As for the location of them...I don't have a clue..

Thanks for checking into that for me.
Yeah, I'm surprised it runs so smooth, too.
That was actually a reenactment of what happened 5 minutes earlier, kinda like the Iwo Jima photo.
The first firing burned off the Marvel Oil and wasn't so smooth the for the initial 500 RPMS but it levelled right off.

I didn't really expect it to fire up at all the first time so I had to run inside and get the video camera for the second firing.

It's a rainy day here today but I suppose I'll have to get under the Caddy anyway to see about the leaking antifreeze. I've found out I can't get a fuel pump until tomorrow so I guess I'll go order it and try to figure out some of the other situations like why I have no dash lights etc... Horn, blinkers, map light,headlights and brake lights work, but no dome light?? Maybe some bad grounds. I'll jiggle a few things and see what happens.

Catcha Later...

hey mojo, great news, your persistence is paying off. let the caddy eat!:D

Here's a walkaround video.

http://www.youtube.com/watch?v=ypftGGOG1is

Today I fix the master cylinder and put on a Caddy carb from a 1959, same carb number. We're back to 100% Caddy....
Thanks to all for the encouragement and tech advice!
I'll post a maiden voyage video soon after the brakes are fixed.