I think i found a COPO engine Weird suffix

[mockingbird812]

Originally Posted by Woj

Back in the early 70's, my brother spun the bearings on the 396 in his 69 SS Chevelle. He went to an engine exchange in Cleveland and bought a 427 out of a wrecked 68 Chevrolet Cleveland Police car. I just checked with him and it had an IS code on it. I've also seen multiple times where Tonawanda used a number in place of a letter, so I'm betting your I5 is an IS engine. By the way, it was a two bolt main car that he couldn't destroy. He and the next three owners tried, but that engine never failed.

Phil W.

Cool story Woj - the fact that your brother remembers the engine code from 40+ years ago......priceless!!