i have a stock 96 civic dx and am just wondering what size my alternator is. I will be putting in an Alpine mrv-f450 which is going to draw 400-500+ watts. i would consider buying a bigger alternator, but the amp really isnt that big so i am hesitant. i have a yellotop battery if it makes a difference in compensating for a small alternator.
that amp pushes 200 watts RMS, thats like 16 amps of current draw, you should be fine if thats the only amp you are using in your system. your stock alternator is prob 70 amps, don't know for sure though. my 92 accord had a 70 amp alt in it. and the battery doesn't make up for the lack of a HO Alternator, but will be better then a stock one since its a deep cycle and can handle the charge/discharge better.
acctually my amp pushes a bit more than 200 watts rms. it is 400watts rms, and being an alpine amp, its going to put out more than it is rated for unlike some other amps.