I second Dog Days the one wire alternator does not charge below 1500 RPMs roughly they didn't do great for daily drivers that saw a lot of around town use sitting at traffic lights and what not ask for your amperage I have a 140 amp that I robbed off of a Ramcharger that was outfitted for fire truck use I believe that it is a Mopar product but I'd have to double check for you I run an electric fan a 500 watt amp and AC with the headlights on it sometimes Cuts in and out at idle but driving is fine and charges just to give you a point of reference