Yes, it's based on your knowledge of your motors, run time and size of track.
On our track 110'x36' indoor carpet I try to stay around:
Mod 10 turn - 1.38 - 1.4" or 35mm rollout
Stock (Monster) 1.57 - 1.59" or 40 mm
Stock (MVP) 1.65 - 1.67" or 42 mm (Yes, I still like the MVP,
especially on real tight tracks. The ones I have are really torquey)
I have charts made out in excel in anyone wants a copy just email. I print them with a few different spur gear sizes and tape them to top of my box then it's quick at the track if I change tire sizes or winds of motors
take care
john