Hi everyone,

I’m seeking assistance in identifying my Oldsmobile 455 Rocket engine. Here are the details I have:

- Block Number: 5238295
- Head Number: 411990 D3BS
- Other Block Number: 395558 2

The engine is equipped with an original Rochester Quadrajet 4-barrel carburetor. The valve covers are painted light blue. Could anyone help me determine the production year, version, and specifications of this engine based on these numbers?

Any additional insights about its potential performance would also be greatly appreciated. Thanks in advance for your help!

Best regards,
Norbert

 

395558 2 is the block casting number for a 1968-1976 350 engine. Not a 455.
The year of manufacture will be stamped on the VIN pad near the #1 cylinder. The head number is also in that location. Small blocks use a number whereas big blocks use a letter.

 

Sh*t... I have provided you the wrong data. That was my previous engine, which was indeed 350 🤦

Project of rebuilding my car is already taking 7th year, so I have forgotten that these were taken from the one before swap. Sorry for the mistake.

I will come back with numbers update within 24 hours.

Thanks for quick and precise reply

 

Post photos of the casting numbers and VIN derivative stamp to avoid transcription errors.

 

396021



Most probably 34-121412

 

The VIN derivative looks like 34E121112. The 4 designates the 1974 model year and the E would be Linden, NJ assembly plant. The J heads are consistent with a 1974 model year motor.

 

I can't fully agree with your opinion, because the numbers are actually 34 121412.

Between numbers I have to agree, that this bar "-" it might be as well the top of letter E, F or T. Let's wait for some other opinions.

 

"F" and "T" were not used for any plants that built Oldsmobiles in the 1974 model year.

 

The only plants that built Oldsmobiles for the 1974 model year were:

Linden, NJ - E
Framingham, MA - G
Van Nuys, CA - L
Lansing, MI - M
Willow Run, MI - W
Arlington, TX - R
Fairfax, KS - X (sorry for the typo earlier)

If that faint letter isn't an "E", then which of these do you think it is?

 

3 Olds,
4 1974,
E Linden, F Flint.
What are the other engine plant codes that may resemble an E or an F?

The last 6 aren't relevant IMO unless that can be narrowed to certain models by the # range. Can it?

 

Good, this is an actual clue. I did some filters/editing with the picture, it might be a little bit of a help. Unfortunately the numbers are double stamped in some strange, unclear way. With your conclusions regarding letters, the full number would be as follows: 34E121412

 

With Joes info F can be taken off the list.

 

Curious to know what model & year vehicle houses this beastly piece of iron?

 

Not for Linden. In any case, Linden only built B-body Oldsmobiles for the 1974 model year.

 

Currently this guy:




'48 Pontiac Streamliner Coupe

 

Currently it lives peacefully in '48 Pontiac Streamliner Coupe