well my crank i believe is a standard PSD toothie 1. it has 53 teeth. and the charger pulley has 24 teeth.
i have just been in touch with "LregG" and he says his was running 19psi with a 51mm throttle.
i have just gone over some old photos and he has 24 teeth on his charger pulley by the looks of it.
i have asked him for a couple of photos to confirm this.
EDIT! - just found this on Club polo - someone called milgo was selling it
its the same - after painstakingly counting them sodding teeth - 53 & 24