Which one, the evaluation one or the ranking?
Be prepared for a very annoying explanation
The evaluation one.
I developed through some weeks an empiric formula (nothing to do with ProfessCars of
www.automobile-catalog.com) which takes count of a lot of parameters: power, torque, weight, drivetrain, width of the car, tire size and compound, height (as an estimation of center of gravity). The result is a good prediction of the car's performance. Sometimes more accurated than PP, sometimes not.
I did it before the introduction of PP, and the much of time was collecting IRL car data. I find it very useful to compare production cars with legit tires with racing cars, as it is impossible now with the new PP system. Also will have to adjust some parameters in the future, for very extreme cars.
The ranking one.
I selected 10 of my fav tracks, which are also sample of a track class (from slow to superspeedway). Also took in count how much the circuits in a track class are important in A-Spec (ie how many times it is used in A-spec). Laptimes are then normalized to a standard track lengths.
So, the ranking points are a weighted average of the 10 lap times, normalized another time to be near the PP value. This value is balanced before PD decided to not take in count tires, or better, to standardize PP values with an unknown tire for all cars (Racing hard? Sports soft? Who knows?).
I developed this system for GT2. In GT4 first, and GT5 after, only had to update track data.
Both formulas are in ods format.
I wonder if someone read it all