ive got 600 - 650 watts on a stock alternator in a f150 . I have a pioneer deh 7700 and its got a battery voltage meter and when i get to about 53 / 62 on a good bass songs the lights start blinking .. not crazy bad but they do lol ... but ive never saw it drop below 13.9 , 13.8 .. is this alright ? if i upgrade the big 3 you think i could handle 900 watts >