Packard Forum Index » V-8 (1955-56)

I just purchased a Packard V8 to put into my 1949 Studebaker R5 and need some help identifying the engine. I am new to the Packard world so I am looking for some assistance.

I took the engine apart in my shop yesterday and cannot locate the engine id number. I have the cylinder head numbers which referenced the 1956 big valve head. There is a casting on the rear of the engine that is 101855 440971. The cylinder bore is 4.125 and the stroke is 3.5 which when looking up the Packard V8 information appears to be the 374 engine.

Any assistance that someone could provide would be greatly appreciated.

Thank you,

Steve

It should be a 1956 374 V8. What is the number near the oil filler tube of the form 56nn-nnnn.

look at this for more info on engine numbers and pictures of number locationS:

https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?topic_id=2789&forum=14

Do u have the oil pan removed????? We need to discuss the oil pump as they were a weak spot in the engines.

Are u doing your own work or farming it out???

101855 is the casting date, 10-18-55. The motor number which should match the vehicle number should be above the water pump manifold on the flat surface where the oil filler tube is mounted. The Utica engine manufacturing number should be on the passenger side at the rear, on an ear of metal just below the cylinder head. That said, these numbers sometimes appear in other locations so you may have to look around a bit if you don't find them where I've indicated. Photo of the Utica engine # enclosed.

If the motor was built as a 374, the Utica number will have a C or D prefix and the the motor number will begin with one of the body prefixes for a senior Packard, 5682, 5687, 5697 or 5699.

EDIT - of course it's possible to have a 4-1/8" bore engine that was a 352 engine subsequently bored from 4" bore, but I think your engine casting date precludes that.

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Welcome to the club! Your R5 is the short box 1/2t, correct?

FWIW, I have a Packard V8 ready to go into my '55 E12 Studebaker 3/4t truck. Let's keep in touch as we build along together.

1. The 374" has 10:1 compression ratio which is too high for today's fuels if you plan to use it as a truck and pull a load. Running unloaded, with premium fuel and a custom ignition advance curve, you might get by.
b. The '55 352" heads have larger combustion chambers and can be retrofitted with '56 valves if you feel it is worth the effort. Not sure I would if the '55 heads have good valves in them.
b. The '56 combustion chambers can be enlarged by hand grinding to lower the C.R.
2. Which transmission do you plan to use? The R5 is geared far too low for the Packard. You'll need an overdrive and the OEM Borg-Warner T85 is perfect. Do you have the standard shift bellhousing and flywheel?
3. What are you going to do about the brakes? The Packard, properly geared will quickly outrun the little 1/2t Stude brakes. Since the rear axle has to be changed anyway, better brakes back there come along with the deal.
4. The 374"s usually had dual exhausts. Since the C-cab has the fuel tank on the driver's side of the driveshaft, it will be easier to fit a single exhaust down the left sid, so find or order the single kit. Use a 2-1/2" or 3" muffler and tailpipe and you won't notice any horsepower difference in normal driving.
5. The tapered axles in your rear end won't last long under Packard torque. Plan to upgrade to flanged axles or replace the entire rear axle with a stronger one. If you're not using an overdrive transmission, you'll want rear gears around 3.07 to 3.54.

thnx, jack vines

Hello everyone,

I am looking for the casting numbers now since I know where to look with all your help. I havent gotten the oil pan off yet.

My father owns a full machine shop and is going to do the rebuild for me on this one. He has built all my "roundy round" engines in the asphalt modifieds and asphalt sprint cars I used to race....gave all that up to work on this Studebaker pickup!

I can tell you the cylinder head casting number is 6480406CD

It was quite interesting to see on this engine no valve notches in the pistons which was really cool since I didnt have to run valve nothes in the small block Ford 427 I ran in my asphalt modified....hadnt seen that in a while.

As soon as I find the casting number on the block I will let you all know what I have.

As far as the truck build goes (yes it is the 1/2t shortbed) this is what I am doing:

I have the original flathead 6, transmission and rearend so I am rebuilding the original fram and suspesnion and have it ready to mount all the sheetmetal on.

For this Packard Engine I am building a square tube chassis with coil over suspension and a Ford 9" rearend.

I am not going to manipulate the body at all on this truck and want to be able to move it to the original frame at some point in the future, but for now want to have some fun with this project.

Steve

I'm curious. What made u decide to buy a Packard V8 engine to put in the Studebaker truck???? WHY the Packard V8???

"For this Packard Engine I am building a square tube chassis with coil over suspension and a Ford 9" rearend"

BE FORWARNED!!! That altho repop replacement pistons ARE available it is HIGHLY controversial as to whether they are suitable for anything more than rather subdued driving demands.

Rod bearings a are another issue.

Quote:

I can't answer for the OP but here's why I'm doing it:

1. The Packard V8 engine generates 50% more torque than the Studebaker V8s. Since they cost about the same to rebuild, why not go for the super size?

2. The Packard V8 was a natural upgrade for the larger Studebaker trucks. However, since by 1956 S-P had decided to get out of the automotive business and thus closed the Packard foundry, it never happened. Since Stude never got around to doing the right thing, I'm doing it.

thnx, jack vines