I found this data on the forum
117: 52.6cc combustion chambers (measured
using a non-medical syringe).
The 3.5 116 heads are ~38.4cc (this data could be from Tomguy?)
And I guess both are D-jet.

I am not sure how this data goes along with Tony's 45cc for the K-jet 117 head.
But obviously there are differences in the types of 4.5heads? Are there D-jet and K-jet type heads and what is the differences exactly? Was the Compression rate the same on both versions of the 4.5?