The esc is rated for a certain amount of current draw or load going thru it. That is a 1/10 car esc. They use the higher rpm but less torque motors that are rated as 3300, 4600,6500 etc. They will turn more rpms in a lightweight car and go very fast. For a 1/10 truck you will want a motor rated in the 1800-3800 range. 1800-2300 would be for like a monster truck or crawler, basher used in grass , dirt and a street type truck or 2 wd will go a little faster with the higher rpm motors like 2600-3800. You want the esc to match the motor as well as you can. I still dont have my mamba in my slash tuned perfect with the gearing and timing perfect but they can be very fast with the right combo.