kv ratings are often on sensorless speed control/motor systems, I am not a fan personaly but for racing reasons, otherwise they are good systems, Mamba Max is probably the best out there.
lowest turn motor is 2.5t, but you need really good batteries to have this going, otherwise you could do damage to basically everything in your car, especially if you start playing with motor timing.
is it drag racing you are looking out? what car will you be using?
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