stephenfleming

iTrader: (1)

forget the cap.
get a better ground.
at least do the ground from the battery to the chassis.

SoundVue

In a DC Circuit, (Car Battery to Amp) it acts as a battery. In AC its a filter. This is DC application not AC. you are not going from the ALT to the amp. than ks anyways

danyman

iTrader: (1)

the alternator creates an ac feedback that does get filtered by the battery but there is still a residue of it and is harmful to SQ

anyway do your homework on the ac ripple from the alternator and come back and talk i shitting you lol even better grab a osciloscope and do the test yourself with a cap and without

danyman

iTrader: (1)

even better ill stop it right here and tell you what you want to hear. since your running 500watts rms amp yes a .5farad will be just fine as of recomendation i dont know just make sure the ESR is very very low to be affective and check if it was tested at a lower voltage than 20volts cause they say its .5 tested at 20volts. soooo what is it at 14.4 volts??? .1 maybe just check anyway good luck