Wasn't the factory setting 4000rpm?
I use to set mine with a quick rpm induction clip on the plug wire. Slowly rev the motor and watch the sight glass on the PV to close. Just lock it down at 4000rpm. Never did count turns. Don't see how any two would be the same. How clean your PV is, how old the spring is, what start point to turn..
Wouldn't the PV setting move with the pipe? So a 5700rpm close wouldn't be best for someone that runs a FMF, PT or non high rpm pipe.
A setting of 1 turn (5700rpm) with a PT pipe would have a dyno run that looked like 1.25 turn with a Q pipe. You held the PV open to long