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Hello,

I inherited a 49 Chevy truck. I just got it back to my house, trying to figure out what I have and where to start. The motor is a 390 Cadillac that my Grandfather put in in the 1960's I think. My Grandpa passed away, my uncle passed away, my Dad passed away.... so no one really left who has any history on the truck. I really like the idea of a Cadillac motor but I wonder if the expense is worth it or if I should just swap to a small block Chevy since parts are so much easier to come by. I'm assuming these mounts are fabricated, these are not the original mounts, are they (see pic)? Does anyone else have a Cadillac motor in their truck? Is the expense worth it? The motor turns over with a wrench so it is not seized but the freeze plugs are all missing and the truck has been sitting outside for more than 20 years so I'm thinking the motor will need to be rebuilt. Overall the truck in ok shape, lots of surface rust but no holes that I can see. Thank you,

Great conversation rig for sure. You just know there are some great stories that may well have been lost to time. That said, check with the wives. They may have prove to be a surprising source of info. Failing that, inquire about friends/buddies of your Dad and Grandpa. I'm betting someone has stories to tell. You never know, with a little sleuthing you may find someone that helped with the build. I've been elbow deep in several projects with buds when their kids were too little to know what was going on or were still in the future. One day I'd love to share tales of helping their dad back in the day.

Good Luck,

RonR

The 390 is one of the very best engines Cadillac ever made. It was the last of the series of engines used in Cad and Oldsmobile from the late 1940's to the early 1960's, ones designed by the legendary GM engineer Charles Kettering. If the engine is still able to turn, I'd suggest trying to get it running- - - -its condition might surprise you. I've got a 61 Cadillac 390 sitting in a motorhome my father spent many years building from a Cadillac hearse chassis and a Spartan aluminum-skinned mobile home. Dad's health failed and he never got his project on the road, but I haven't been able to make myself haul it off to scrap. He put a huge amount of work into it, including doing a massive amount of dyno run time on the Cad engine. He adapted a Quadrajet carburetor to it and jetted it for the full range of performance, from idle to wide open throttle. The torque numbers were impressive!
Jerry

Jerry, sounds like a project for your old age. Drag it to the shop and finish er in your spare time.

49Shep, you are correct, the mounts are fabricated and not original.

At the rate I'm accumulating projects, I'll have to make it to well beyond 100 if I don't take on any more anytime soon! 72 and counting- - - - - -!
Jerry

Since you are near the ocean, there might be salt damage, try to get it running to see what results you get.

Ed

Cool! Thank you. Sounds like the 390 would be worth trying to keep. Many thanks

Some of the earlier, smaller displacement Caddy engines from the early 1950's found their way into 40 Ford coupes, with about a hundred gallons of moonshine whiskey in the trunk.
Jerry

Seems like that is an interesting swap there, I would try to get it running reliably since it is already in the truck.

Also, how fast ya really wanna go in a '49 chevy truck? I can run my '65 C10 on the highway, but it's noisy just from all the wind noise...

great place to read up on & learn about the Cadillac engines:

Cadillac Engine forums

My ex wife number 2 Dad had a 39 Chevy coupe with a Caddy 390 in it! Saw pictures were he used to drag race it at a local strip. He passed away before me and it sat for 10 yrs. outside I decided to get it running and did! Loved the concept of hooking the motor to that Coupe and driving it knew it was very strong. Information on it was gotten from his old hunting buddies great stories! They said the secret to that motor was he bragged about having the heads milled! Ok she ran off never got to finish it and her new family sold it! Grrrr

Used the next generation 425/472/500 Cadillac engine in a 51 GMC that a plumbing company owner carried blue prints around to all the jobs. He had 63 crews so miles piled up in a hurry. The original 472 wore out at around 160k miles and was replaced with a 500 that has near 200k miles on it. These engines are not as wide, long, or heavy as one would expect and the accessories ( p/s, a/c, and alt) are tucked tight around the front so swaps aren't as hard as some other engines with way less torque.

I had a virtually unused 500 and a Turbo 400 trans that was intended to be installed into my 59 Suburban. Unfortunately, some metal buzzards got into my storage area and carried it off, along with a few other engines. I assume they got sold for scrap iron! I've got a 1970 Fleetwood Brougham with a 472/400 powertrain that will probably get used for that project, but it's got about 250K miles on it! That one will need a full rebuild, engine and trans.
Jerry

Many thanks. My apologies, I don't seem to have it set up where I get notifications when people respond to a post. There was a lot of white creamy stuff in the oil and a lackluster attempt at a compression check was not promising so I'm going to set the motor aside for now. I got one quote to rebuild for $5000, I'll call around a bit when I get to that place. For now I'm getting the frame ready to be blasted and powder coated. I'm pretty sure the transmission and rear end are out of the Cadillac as well. Hotrod Lincoln, I'm curious in another post you stated that putting in IFS was a mistake in your opinion. Why do you feel that way?

49shep, buddy you just opened up the Pandora’s Box. HRL has stated dozens if not hundreds of times his theories on IFS conversions. This always ends up in hurt feelings and bruised egos among the two groups (modifiers and restorers) and has in the past caused threads/posts to be deleted/locked by the Moderators. Be aware ahead of time that things may get heated. 🛠

Ha! It’s ok, I’ve been married 20 years and have 4 daughters, I have no pride left, simply the shell of a man. I think I’m looking for an excuse for sticking with the straight axle. I think the straight axle with a Cadillac motor would give it that old school hot rod look. I do need to rebuild the front end and probably go with disc brakes at least. CPP has a whole ifs plus rear leaf kit all for $2200 so it is tempting....

I'm not necessarily opposed to an IFS, as long as it's from a truck, not some subcompact car. What does get me upset is the nose-dragging stance most IFS systems end up with- - - -looks like a hound dog that just had a close encounter with a skunk! If I finally get around to putting my Burb back on the road with Cadillac running gear, I'm planning to install a narrowed 3/4 ton IFS from a mid-1980's C-20. I'll probably graft on the complete front frame from about the firewall forward, but it will need to be narrowed about 6" or so to make the tires fit the fender wells. The Burb already has a GMC 3/4 ton Dana type 60 rear axle with a limited slip center section so the 8-lug front end will make it a full-grown truck, not some sort of Cowboy Cadillac with pony car suspension.
Jerry