EK011 KSS/KTS ENGINE

I am looking for the engine balance factor for a KSS (1936) Mk II engine
Some time back I made a similar enquiry for the MAC motor. After many bits of correspondence it appears to be 70% and if it is of use for the MOV it is 85%.
The latter I found in one of Irving’s books. - Leo Middelberg 2/12/2007