At what point will the stock alternator not cut it anymore?

[CombatComProg]

I'm purchasing a major system with a top of the line Pioneer head unit and two amps to power 2 Infinity Kappa Perfect 12" subs & all of the infinity loudspeakers going in the car. At what point am I going to have to invest in a new alternator. Nothing is installed yet. Should I get one ahead of time? Thanks!

 

[6APPEAL]

In my experience, the factory alternator will last with up to about a 250 watt system, if it is not pounded on all the time. I would say go ahead and get a good alternator. I would also invest in a very good battery or two. HTH

 

[CombatComProg]

There is going to be a 1000 watt amp powering the subs and 200 watt amp powering the loudspeakers. What kind and power of alternator should I get?? What effect will a high amp alternator have on the rest of the vehicle? What will happen if I get a smaller pulley for the alternator? Thanks!

 

[6APPEAL]

I bought one manfactured by PowerMaster from either Jegs or Summit. Very good unit. I bought the 200 amp one that has the black heat coating on it. The only thing I had to do was upgrade the charge wire going from the alt to the battery (4 ga). Other than more amperage you should not see a change to the rest of the car (ok, except maybe brighter lights). A smaller pulley will not buy you anything. The factory alt is designed to put out 125 amps at ~14.5 volts and that is all you will get out of it. Spinning it faster only gets you to that point faster and wears the bearing out faster. Also might overheat the alt. With the power you will be running you really need two batteries.