It should have a 366 big block, that's what replaced the 348 in 66. If it was a twin screw it could have a 427 in 69. Either way congratulations on scoring it. I have a 72 C-60 with the 366 and working 4th 5 speed. I also have a 65 C-80 that I restored for my dad a few years before he passed away. Clean it up good and make him glad he gave it to you, you'll be glad you did.
Yea Marl it has a 366.I made a typo.It does have the twin screw and we assumed it was a 427 when we got it 20+ years ago.But when dad had some motor work done several years back the only thing that would work on it was 366 parts.
