Measurement Required for pr3 head

[tofuR]

Hey guys..
ive checked the helms manual to no avail..

does anyone have a pr3 head sitting around ..
or does anyone know ..

what the distance from the intake valve to the actual port is ?

i've done a very dodgy measurement myself just buy guestimating on top of the valve cover at about 70mm but i'd like a more accurate measurement if possible..

thanks!