HI a couple of weeks ago i bought myself a Oldsmobile holiday coupe super 88 from 1956.
I'm checking things out and I was wondering where I can find the engine number and how I know that the engine is a original rocket 88. The only number I found on the engine so far is on the righthand side of the Block .
number is B098521E.

could anyone help me please

 

Welcome to CO, should introduce yourself in the newbie forum. Answer your question, the '54 to '56 block is green and 57 is gold, casting number is on drivers side of block between #5 and #7 cylinder.

 

It's not possible to pin down your engine number if you don't have the original build sheet.You can tell if the engine in your car came from the same year as your car by the head numbers, carb and intake numbers and other small changes that happened through the years but the engine numbers don't match anything else on the car. So matching numbers really means nothing on a fifties era Oldsmobile....How about some pictures, we love pictures.... Tedd

 

If you can get a 1956 Oldsmobile service manual , there will be a section in the front of the book that explains the engine number .

https://www.ebay.com/sch/i.html?_fro...anual&_sacat=0


The letters before and after the numbers will determine the year , as well as the carburation and compression of the engine .

 

Hi thanks allready for the reply guys.
I posted an introduction on the newbies forum
https://classicoldsmobile.com/forums...6-belgium.html
the first thing i bought was indeed an service manual Charlie but that's why i was not sure from the engine.
During the time the last owner did some work on the engine and it has been repainted. He changed he carburator and air intake.Luckily i've got the orignal carb the Rochester 4 barrel and oilbath intake so i will be replacing them.
When i was reading the manual i read that the engine numbers should be starting with a V 1 en then numbers, so i begon to search, the first number i found was B098521E. but thanks to the reply's(classic muscle) i found an other number between the 5 and 7 cilinder.



@Tedd thanks for the reply, i've read on the web indeed that rocket engine's from that period should be green or gold but because it's been repainted( you can see on the picture below) i was starting to have some doubts.
Now the car is from '56 refuring to the chassisnumber and on the engine is the number 572461 could it be the corrected one? An other thing becaus i was incertain is that their was no "ROCKET" on the valve covers....




what do you thing???

 

That looks like a 57 or 58 371 to me. I will check some numbers when I get to my shop tomorrow.

 

That 572XXX number sort of dates that manifold from about 1958 or so .

I checked another source , (the H.A.M.B.) and B-001001 and up is a 1958 Olds 371 .

 

What is the number on the heads? #10=56 #16 would be a 57-58. That would only tell you what the heads came from but might help pin down the year of the engine some what. Those valve covers do look like 371 covers but you have a Frankenstein engine so it doesn't really matter. If mine I would be hoping for a 371 and a gain of about 60 hp over the 324.... Just my thoughts..... Tedd

 

324 engine sequence number is on the deck surface on a boss seen looking down between cyls 1-3 right above exhaust manifold. To the other guys point 303 is seen same way but cyls 5-7. Sometimes the engine might have been decked in a rebuild with the number stamping then missing. Good luck

 

Hi thanks a lot for the info . like you can see on the picture below i can conclued based on your info that it is a 57/58, 371cu.
So indeed a gain some Horsepower.Cool!!
I did read on the web that you never can be shure with a fifties period engine/car that everything is period correct.
Fortunaly i know now what kind of engine is in my car, important for ordering stuff.
Now a have a new question : is there a big difference in 324/371 for stuff like sparkplugs and such because i have a manual for a '56 er with a 324 engine...
thanks a lot allready you guys for helping me out. i can see a big 16

 

You will have higher compression and will probably need to use 93 octane gas. Plug wires should be the same also the points, don't know about the heat range on the plugs you will need to check at your auto parts supplier or someone here will chime in. Most of the engine is the same on the outside except it is about a inch taller. Belts will probably be longer.I'm sure other stuff will be different especially when you have to crack it open the internals are quite a bit different.

If mine I would get a manual for 57 just to be sure you are ordering the correct parts. that's a good get on the engine and will make a sleeper out of your 56.... Tedd

 

 

thanks,

 

thanks