its bacially 70 amps per 1000 watts thats if your amp was all the way efficient im guess ur amp is around 80% effcient so for that u would need around 130 amps for the system..... and about 40-50 for the car....... so around 170-180 alternator would be needed that would be if u turned it up all the way..... what kind of car is it? u would probably be safe running a 160 amp alternator...... but im sure that u want components and a 4 channel amp..... so try and get a 200 amp alternator tell me what k9ind of car it is and ill tell u how big the alternator can be
1996 Ford Explorer
Front : stock
Subs: 2 Image Dynamics IDMAX v3.
Amp: Hifonics Hercules at 4 ohms (450 watts)
soon to come