Distance from front axle to center of aerodynamic downforce is the shortest distance from the centerline between both front wheels to the point on the same horizontal level where the sum of all aerodynamic downforce is projected.**

If there are no wings on the car and you have no data resulting from wind tunnel tests, disregard the downforce by entering a zero ("0") in the "Aerodynamic downforce at top speed" field. As a result, the value of the "Distance from front axle to center of downforce" field has then become irrelevant.

Without wings, there probably will be some negative downforce (lift) at higher speeds, most likely on the rear end of the car, but there is no way of guessing in the right direction without any further tests.

** In case your car not only has a rear wing, but one in the front as well, the Center of Downforce (x) can be determined as follows:

x = a – (F_ADF / F_ADR) • b

x = distance from front axle to center of aerodynamic downforce
a = distance from front axle to rear wing point of action
b = distance from front axle to front wing point of action

F_ADT = Total Aerodynamic Downforce

F_ADR = Aerodynamic Downforce from Rear wing

F_ADF = Aerodynamic Downforce from Front wing or splitter