If you know the manufacturer then you could call a dealership parts department with the engine number and they should be able to tell you.
You could also do a google search saying engine serial number and add your number and see what comes up. You'd be amazed at the information out there on the net.
I'm assuming that you don't have contact with the owner of the 78 Oldsmobile? The simplest thing would be to ask them.
Hope this helps.
〉 Answered on May 6th, 2007 by Lori Johnson, Owner and Instructor at Ladies Start Your Engines