i own a 1979 elcamino with a 305 v8. i decided to go with 2 15s. this is what i got.
160 amp alternator. 2 optima yellow tops. 1 for the car itself and 1 for the system. i have 0 gauge from one optima to a switch (fuse) to the isolator then to the 2nd optima. from the 2nd optima 4 gauge runs to a 5 farad power acoustik cap. from the cap it goes to a 2300hct 2 channel audiobahn amp. from the amp (bridged) i have 2 15'' power acoustik mofos.
the main problem i am having is at idle the batterys are not charging well. at idle my cap will read 9-10 volts while bassing hard. my cap will read 10-11 volts wile driving 20 to 40 mph while bassing hard. on the freeway my cap reads 11.5 while driving 60-90 mph while bassing hard.
i think it could just be my alternator. a audio place told me to run a stinger battery and a stinger 5 farad cap and that will solve the problem, and it is not the alternator. he also said the optima is not a good battery to run with a sound system.
should i just run a bigger alternator? what kind? does it charge at idle? please help answer my questions. this car is a daily driver and i do cruze alot.