head shapes/volumes/squish???

[mgtkr1]

having just removed the head off the kr to check for signs of det,colour etc i put it next to another head to compare as i know the 'other' head is modified. the second head has a much wider squish band and appears to have much more of a dome. could someone please tell me the std witdh of a kr squish band? the first is approx 4.8mm the other is 6.8mm. any theories of desired fuel,piston type etc etc. a shot in the dark i know. will measure the volumes of both if i can find a burette unless theres alternative ways to measure?