Are these the small valve engine heads for this year? 1.72? If so can valves be upgraded to larger size at machine shop? Just Learning!!!!
Thanks,
Steve

65 327s did have 461's. Most 461's are 1.94 in, 1.5 ex. They could also come with 2.02 in and 1.6 ex. You can stuff 2.08 and 1.625 if you really want to, but the heads will need machine work under the valve seats if you go bigger than what came in them. Have them magnafluxed and the guides checked before thinking about doing any machine work on them. It's often cheaper to buy new heads than to rebuild your old ones.

Thanks John! Good Answer!!!!!!!!