I picked up a set of C80E heads but am confused on the specs. They have no 4V or double dots over the 289 and do have one M cast under a port with "4" under another, but they are closed chamber. They seem to contradict what info I've found about them. I haven't measured, but it appears they are the 54cc variety. Who has the real scoop on these? I also have to see if they have hardened seats as the PO had a bunch of work done to them.

 

It sez here that the C8OE-M head is the garden-variety 68 289 2V head, with 63cc chambers and 1.78/1.45 valves.

 

QUOTE=2+2GT;7133124]It sez here that the C8OE-M head is the garden-variety 68 289 2V head, with 63cc [/QUOTE]

Exactly. So who can explain the closed chambers?

 

Closed chambers were normal, even on 2V engines. That open chamber stuff didn't happen until 1972, when emissions regulations killed compression. And performance.

 

OK, so you can get 53, 54 and 63-4 CC all in closed chamber?

 

Yep. Don't forget the early 289HP, 49.2cc.

 

Does anyone see what I'm questioning? I agree, the data says these are 64cc heads and I'll check them should I ever get a moment to breathe, but who can argue the port shape is the same as the 54cc 4v heads, even though these obviously aren't 4v heads. That's why I ask "what's going on here?" My ports are the same as B to me. The pics suck as they are reduced, but my chambers have the downward left side sweep as in B and not the symetrical shape as in C. Can anyone argue that? Like I said, I'll whip up some CC tools just for grins. Something just doesn't add up to me with the numbers.