The invention provides a low modulus drive belt for an automotive accessory drive system that allows for relatively high elongation during installation and that maintains a relatively high percentage of its install tension throughout the useful life of the belt. The invention also provides an automotive accessory drive system that utilizes such a belt and a method for constructing such a belt. One embodiment of the invention is directed to an accessory drive system for an automobile that includes: (a) a drive pulley; (b) an accessory pulley operatively coupled to an accessory drive shaft; and (c) an endless drive belt engaged between the drive pulley and the accessory pulley, where the drive belt includes an endless band of rubber composite material having a plurality of circumferentially extending an axially aligned polyamide 6.6 twisted cords formed therewithin.
