I still wonder why:
Factory SB 116A Dec 1952, states this: "The following were the correct compressions (in lbs/in2) with the plugs removed, the water outlet temp
at 70 deg, and rotated on the starter:
Mk VII XK120
7:1 110 105
8:1 120 120 "
SO…why 120psi as the factory spec compression with the 8-1…yet it seems the compression later and seen in forum posts is 150psi ?
Nick
Heads milled? Thinner gasket? Maybe B-Type cams had different specs to earlier cams, affecting dynamic compression? I measured 165 on all cylinders on my 120, but I forgot to do it with the throttles wide open, so maybe that made a diffrerence…?
Chris