[C3H8]

batteries! good topic. i subscripe to the recycle type of mindset, i am cheap too. so i always buy junkyard batteries. they are $20 each, and i will only buy a battery that is 6 months old or newer. i abuse my batteries pretty bad, but they still last about 3 years a piece. i think this is due to the increased size that i use. let me explain.

my car has the battery UNDER the driver side headlight, in front of the wheel, and its inside the front bumper. kind of an odd place, but it helps create more engine room.

due to the limited size area in there, i cannot upgrade to a larger battery, but i can add extras! i added 2 diesel truck batteries to the trunk of the car and i put them in those plastic boat battery boxes. i ran 2 gauge cable from the front of the car to the trunk for my 2 extra batteries. my alternator is about 90amps max, so it charges all 3 pretty good. i am guessing the extra batteries and cable add about 70 extra lbs. but running alternatorless more then makes up for the weight penalty, with increased mpg's. remember my car is about 3000lbs, so an extra 70lbs is nothing. i don't even notice it.

the reason i have extra batteries is because i remove the alternator and a/c belt in the cooler months. during the summer i just disable the alternator with a switch on the dash so i can keep using a/c. since it's summer right now, i have the alternator switched off but still i use the a/c. i also turn the alternator ON when coasting to a stop to help keep the batteries charged. (part of the reason i change the charging voltage to 15.5v is to help charge those batteries quick under the situation when i am coasting to a stop and charging the battery at the same time) as soon as the engine rpm's drop to idle and i stop, i turn the alternator switch back off.

because of my nearly constant a/c usage, stereo, 12" sub and amp, headlights, etc i find that having 1 battery is not enough for running alternatorless in my car that seems to take a million amps. deep cycle batteries are too expensive. so junkyard batteries it is then! on a cool day with a/c off, subwoofer disconnected, and only the stereo on i can drive for a few hours with no alternator. but this is torture on normal batteries that are not of the deep cycle kind. that is why I chose to use larger diesel truck batteries. they store more energy, and are more forgiving when deeply discharged, and at the junkyard all the batteries are $20 each no matter if it's a tiny honda battery, or a large diesel truck battery. so why not buy larger if they are the same price?

if you do not ever run with the alternator disabled, then there is no point in upgrading to a larger battery, from a fuel economy point of view anyways. you might as well run a small honda civic size battery and enjoy some meager weight reduction savings.