When selecting an electric car motor you have two choices. DC or AC electric motors. DC motors are powered by Direct Current (a battery is an example of direct current) you will need to find what is called a series wound DC Motor. Most DC motors operate from 96 to 192 volts.
AC Motors work off of Alternating Current. AC motors suitable for an electric car are usually three-phase 240VAC types, requiring a 300 volt battery pack.
DC motors have advantages over AC motors in cost and battery pack voltages. Since the DC motor runs at a lower voltage than the AC motor you can use the 6 volt golf cart style of battery. They do require more current than their AC counterparts but the 6v battery happens to have the best capacity rating so this should not be a problem. AC motors, although costing more, do have distinct advantages over the DC motor. For one, they can use the back emf from the motor while the car is braking to recharge the batteries. This causes the AC motor to be more efficient Although they require a higher battery pack voltage, around 300 volts, they use less current than the DC motor and therefore can use the lower capacity 12 volt batteries for their battery pack.
Both types of motors need a motor controller to operate, and once again due to the complexities involved, an AC motor controller is much more expensive than a comparable DC motor controller. Many times you can find very inexpensive sources of motors by shopping around. Due to regular maintenance schedules many industrial areas will have businesses that throw out working motors on a routine basis, which could be a gold mine if you can find and talk to the right person in charge.
Another great source is eBay. Just go to eBay and do a search for DC or AC motor, and you will find many sources to choose from. When selecting an electric car motor you need to do your homework. Many factors come into play such as cost, type of car you are converting, and don’t forget about how much space you have under the hood. Proper planning goes a long way for a successful electric car conversion.