been thinking about buying a new alternator. my stock alternator is 130 amps. i have found 150-250 amps. i run a galaxy 66v ts mod-v and a sweet 16. i have an extra battery with a 2f cap. right now my volts are 14.3 with nothing on and the volts drop to 13.2 when i key up and start moding. how big of one should i step up to thanks for your time and help