so iv been wondering how manufactures rate there brushless motors i know 8.5 10.5 turns and all that but i want to know how they determine if its a 8.5 instead of say a 2.5 is it the amount of electricity it takes to run or what?

The numbers used to designate different motors can be dfferent for different manufacturers. The 2.5, 8.5, 10.5, etc... is the number of times the wire is wrapped in each phase of the motor. Generally in similar motors the lower the "turns" as this is called, the more RPMs that motor will spin for the same voltage. Other companies rate motors by a "Kv" rating. This is the actual RPMs the motor will spin for 1 Volt. Obviously a higher number will spin at a higher RPM.