A "20-turn" single (which is the designation of the Stinger motor) indicates that a single thickness of wire is wound 20 times around the armature of the electric motor. The less times the wire is wound the faster the motor will go.
The thickness of wire around the armature determines how much torque the motor puts out. So, a 20-turn double would provide more torque than the 20-turn single. Remember, a more modified motor must be geared properly in order to achieve its maximum performance and may also eat up your battery causing you to have shorter run times.
The Stinger motor is a mild modified motor that gives you a lot of speed and still gives you around 6-10 minutes of run time, depending on how you have your car set-up and what kind of batteries you are using.
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