cranked her up early morn for a 300mi drive... stopped for fuel 190mi out, she wouldn't crank, got a jump and drove rest of the way non stop, pulled up, parked turned her off and attempted to restart... got nothing. jumped her over and drove 300mi without turning her off. Next morning - nothing... pulled battery returned to Interstate Battery Dealer, tested good, chargered for 2hrs, still good, they say, check alternater, returned home and placed battery on slow charge for the night. Question... why would car run 300mi distances with faulty charging system? If car will run for long periods, alternator is charging to some degree? why dosen't battery take charge generated by alternator and hold it enough charge to provide ample, sustainable and reliable cranking amps?
Car calls for 55amp alt, how does a 80amp alt benefit my situation... should i up grade? Thanks guys.