Thanks a lot for the input guys! It looks like a great forum here - LOTS of good information and knowledgeable folks!

I checked the casting number on Moretec, auto-ware.com, and several other on-line sources and each says 70cc chambers. I also checked 2 books that my machine shop had and both confirmed 70cc chambers and that they were indeed, heavy castings (just like MI2600 said).

Moretec actually list these heads used on 307, 327, and 350 engines. The pair that I have has the late-model style accessory bolt holes in the ends.

I was unable to find any specs on the intake runners. If anyone had those specs and could list them, I'd appreciate it.

These also look like they take the washer-sealed spark plugs. The plug holes have a real flat face. Do any of you guys know which plugs these would take?

Thanks again for the info!