My son is looking to swap the 260 out of his 78 Calais for something bigger. A hardcore Pontiac friend of mine just bought a '74 Ventura with an Olds motor in it that he wants gone. The seller told him it was a 350. I know in '75 they started putting 260's in them, but this is definitely a '74 and they only used Pontiac 350's that year. So....... anyone know for sure how to determine what size it Is? And yes it is definitely Olds and not Pontiac.