double hump heads are called "camel back" heads and refer to the double hump cast into the ends of the head...

This was a quick reference point for many people to recognize this particular head....

these units came on 350hp and other various 327's and I think some 350's....

they had 64cc chambers using them nets 11:1 compression with flat tops on a 350....these heads are getting rare...most of them had 1.94in by 1.5 ex. valves but some few had 2.02's in the intakes and 1.6 ekhaust....most were absent of any accessory holes in the heads while some had them....

It is far cheaper to buy a newer set of heads than to rework these units to todays standards.... and they are restrictive by todays standards.....