I'm familiar with mid 60s dates codes used by Chevy and probably all of GM, did Oldsmobile use codes back in the mid 50s? If yes, what was the format and was it the same whether cast or stamped? I briefly looked at a few intakes and saw the similar "clock" used but could not determine if anything else was present. I'm trying to ensure we pick out all the original parts for an engine rebuild. Thanks.

 

If you are talking numbers matching engine to body... no. But there are ways to tell if a car was put together from a bunch of mixed years, wrong heads, distributor, transmissions etc. All would work and in most cases no one would no the difference but to the experienced eye you could tell it was a Frankenstein car. What parts are in question? We probably could sort most of the parts in question if it was just a comparsion of two of the same type of part ......Tedd

 

Mostly engine and under hood components like generator, starter, Bendix etc. I can ID the original block from the V number found on the pad between #1 and #3 plugs and the original dealer paperwork, however there are 2 or maybe even three sets of heads, intakes. hydramatics, etc, and these are probably a mixture of 55 and 56. The car had a 56 engine and likely a 56 trans dropped in many years ago (needed a valve job) with the originals retained with other amassed "spare parts". Sounds like I should concentrate on the casting/part number since no date codes? I'll have to dig through our manuals and see if I have anything that lists these by year. I've ID'd the original carb from the little brass tag, the distributor by the alum tag around the shaft housing, and Harrison radiator from the tank code.

 

55 heads would be marked somewhere near the middle of the head exhaust side with a number 8, 56 would be a number 10. I think intake manifolds are the same 55 and 56 (someone correct me if wrong on this). Transmissions on a 55 and Early 56 will not have lines for a transmission cooler if you have a late 56 in a 55 your gear selector will read wrong on the dash display and park will be on the far left rather than reverse far right with the key off. Let me and others know your remaining issues and hopefully we can sort some of this out.......Tedd