Consult your vehicle's owner's manual. It will provide the vehicle manufacturer's group size and CCA rating requirements for your car. Or, ask your battery retailer to refer to his battery application materials for recommended fitment. Remember: Never use a battery with a CCA lower than the manufacturer's recommendation. Also, whenever available, a battery with a higher CCA is more capable of providing for the electrical needs of older vehicles, and will not adversely affect the vehicle's electrical system.