What would cause someone to need a stronger alternator. I've been in the 500 RMS range and never had a problem but I'm moving up to the 1300 rms range and I just want to make sure that it will not cause a problem with my new car.

I have a
Kenwood KAC-9104D amp - the specs say >900 watt RMS at 1ohm
Gravity GR-450 amp (so old I cant find the specs) - my guess is it runs at 400 watts rms (800 watt max) and it will be ran at 4ohms so maybe even less

I would like to understand why an alternator would need to change just as much as I would like to know that it wont mess up my new car

 

if you car about your equipment get a voltage monitor that mounts on your dash and reads from your amp or really close to it. if you drop below 12v or some even say 12.8 get a new preferable agm batt up front. if that doesnt solve it get another batt for the rear also agm.
another cheep upgrade is doing the "big3" which consists of a ground from the front batt to alt,front batt to chassis and alt+ to batt +. . if your still getting too muck voltage drop after all that look into a alt.

 

Don't worry with that install unless you're driving a 118hp special

 

If you have a decent size battery and stock alternator you should be fine up to 1500watts rms, if you go past that then you will require a second battery and zero gauge OFC wire. I only upgraded my alternator when I couldn't keep my voltage above 13 volts when driving with load at full tilt.

 

a lot of it depends on what car you have. some economy cars have TINY alternators, while some luxury cars and trucks use very large ones. find out what your factory one is rated. then look at the draw from your new amp. it all depends on current. if the amp you are getting is class D then it will draw less than the A/B amps (comparable power). if your A/C on and headlights running you are probably drawing 60-80 amps to run your car, stereo not included. if you then add a stereo that draws 130 amps and its cranked up (with A/C and headlights on) then chances are you will overwork a typical alternator.

 

Got it, I dont think I will have a problem. This is in a 2013 Camero. I will post picture as I install my setup.

 

CamAro!!!! Sorry that drove me crazy when I had one and people always spelled it wrong.

The alternator should be fine.

 

Lol you are the second person to correct me. I think auto correct spells it that way...

 

I personally know people who have ran 8k doing 156s with out upgrading alternators...batteries go a long way.