Guys,
I'm about to buy what i hope is a 350 Olds engine and box. I've been informed that the casting number is 557752 - 3c.
Now the 557752 seems to say that indeed it is a 350 of around 1980 but i cannot decode the "3c" suffix.
Assuming it has been read correctly, can anyone shed any light on this ?

John

 

All the windowed main 350s from 77-80 carried the #3 identifier. The A - B - C suffix just indicates a minor casting revision. Not a big deal. C probably means it's a late 1980 casting, one of the last Olds 350 gas engines.