jayekub

I'm in the process of upgrading the big three in my TL in preparation for my new amps.
I've never done anything under the hood besides hooking up an amp before, so I'm kinda learning as I go. I'm hoping someone else that's already done this upgrade can give me some advice.

I decided to go ahead and run 0 gauge even though its totally overkill. So far I've replaced the battery (-) wire to the body and the battery (+) wire that goes to what I'm pretty sure is the starter.

I did the (+) wire upgrade without really thinking about it, and then realized that this still doesn't give me a 0 gauge path from the alternator to the battery and amps, so I'm wondering if I need to also run 0 gauge from the alternator output directly to the battery? I'm guessing it was pretty much pointless to upgrade the starter wire...

Also, there appear to be two grounding straps--one that's close to the alternator, and one that's under the air filter near the battery. Do I need to beef them both up, or should I just do one?

jnc2000

The "Big 3" in the car audio world refers to 3 main wires

Alt to positive batt

chassis to batt

engine to chassis



The whole point of the big 3 is to stabilize your system voltage during increase usage from aftermarket accessories.

There are many article out there about upgrading additional grounds but those three primary wires are your key. There are grounding kits out there that do this exact same thing that will cost you up to $100 but you are doing yourself a great thing and saving a bunch of money doing it yourself.

0 gauge is a bit overkill - nonetheless if you ran it stick with 0 gauge. Make sure you get some nice loom and cover it up good. You can replace those additional grounding straps as well. Remember electricity will take the path with the least resistance. What your goal is in all this is to create a better path for the flow of electrons.

jayekub

Thanks for the reply.

My main concern was whether its a good idea to directly connect the alternator output to
the battery. After poking around a little more, I see that that is how the wiring works, but that it goes through the fuse box first.

It's gonna be a pain to fit a second 200A fuse holder in there...

jayekub

Okay, one more question: anyone know how to determine what the max amperage the battery can
take from the alternator?

It looks like Streewires makes a fused battery clamp which would alleviate my space concerns with a second fuse holder. Not sure what size fuse to use though...if its too big I risk starting a fire or
blowing the battery :-/

http://www.partsexpress.com/pe/showd...number=263-651

Looks like I could just attach two ring terminals to the fused screw, one from the alternator and one
to the amps. I already have a fuse in place on the side of the battery box for the amp run.

jnc2000

Use this as a general rule of thumb when working with car audio and fuses.

http://www.bcae1.com/fuses.htm

As far as the the fuse to use on your car. I personally stick with ANL fuses. I believe our alternator is rated at 110 amps (someone correct me here if I'm wrong). ... But the main thing you are doing by placing a fuse on that wire is protecting your battery in the event that that wire would short out (ie. touch ground.). If you install an 150amp fuse you will be fine. If the wire does for some strange reason short - touch ground and it arcs the fuse will blow protecting your battery.

One word of caution. You can use a circuit breaker in place of the fuse. However, be very cautious of the brand you buy. I have seen many breakers fail internally, thus not protecting the circuit that they were installed on. This can become very dangerous for not only you, but your car.

jayekub

Cool, thanks for the info! I guess I'll stick with the 150A anl fuse.