Can anyone tell me an easy way to distinguish a 289 from a 302? I recently purchased a 1967 Coupe with a non-original motor, and the revious owner can't tell me if it's a 289 or 302...
I would tell you to look at the casting number behind the starter. If it is C5AE, it is a 289. (Or a C4AE, but that is unlikely.) If it is a C7, I think it can be either, but more likely a 289. (The number is the actual year of the design of the engine and the 302 was a late '67 engine, found in late model '67 as the 289 dried up and offical in model '68.)
Others should be able to offer more/better hints, but this is a start.
The switch from 289 to 302 was in 68, not 67. In anycase, you can narrow it down with casting numbers, but if it's ever been rebuilt, all bets are off, the only way to tell one from another is to look at the crank casting number.
ive seen a 289 crank in a 289 block but with 302 rods... man what a turd of a rebuild, parts are not the same...... only real way to tell is pull the oil pan and inspect the crank and connecting rod part numbers. you can pull the distributer and see the crank casting number just barley but wont tell you about the rods or pistons.