Ching,
what is operation performance of your drift car? for my own understanding, the recommeded ratio of 8.5t motor is also up to 7:1, why did you use final ratio of 9.xx:1?
ching,
spour gear 86 : 27 pinion gear
front belt gear ratio :39/18
centre belt gear ration : 22/14
rear belt gear ratio : 39/18
thank you for your assistances.