All turn motors have a KV rating also, it just depends on how a company wants to label their motors.
Let me explain:
Castle, and most 8th scale motors are usually labeled as KV only. I think only speed-passion uses a turn denomination for their 8th scale stuff.
The KV-Turn is standard across companies.
The only one I know by heart is 17.5 turn, which is 2200kv. No matter which 17.5 turn motor you get, it will be 2200kv, and vise versa.
Hope that helped.