dodge charger big 3?

first, the battery in my car is in the rear and looks as if its 2 or 0 gauge wire until it gets to the engine bay. anyone know where it reduces and should i up grade it from that point to the the alt? or will what it has now be good enough? also for the engine to chassis ground, would it be alright to ground from the bolt holding the alternator to the block to the chassis, or do you have to do the the one between the trans and block? there are also several wires that look like grounds coming from just the block to the chassis can i do one of these? or any tips from someone who has done the big 3 to a dodge charger would be greatly appreciated.

No such thing as too many grounds, you can add one from the alt bolt to chassis too. That is a pretty good run of wire front to back. Perhaps adding a 4ga from the alt to the battery in addition to the stock. Adding another path would give the effect of a larger gauge wire.

thanks. i was thinking of doing one off the alt, then one off the other side of the engine. both in 0 gauge wire.   and ill try running a 4 gauge wire like you suggested. should i put an inline fuse close to the battery on the 4 gauge or is that not really necessary?

Stop! The big 3 is about replacing the undersized factory wiring to reduce resistance. The key here is adding wire, not replacing factory. If you are not upgrading the Alternator at this point, I would not replace or augment your factory supply wire. If your Charger is relatively new and you still have a warranty the Ground upgrade won't be an issue, New Power wire might. As you said the wire looks to be 2 AWG or 1/0 AWG. If you do decide to replace the supply cable, you need to fuse it at both ends. 1/0 AWG, 250 to 350 Amp fuses will be fine.

well i did the engine grounds and battery ground, decided to do nothing with the alt to bat for right now. but this still made a little differance, my interior lights no longer dim but i can still notice my head lights dimming a little when played really hard, but still not as bad as before. i am soon planning on upgrading my whole system and doing a h/o alt. at that point should i do the alt to the bat, or will an extra 4 gauge like mentioned before be good enough?   and can anyone suggest any good places to get a ho alt? i found a place online "mr alternator" has anyone ever delt with them?

That would depend on the alt. At 200+ amps and the long run, I would use a minimum of 1/0 wire. I would also keep the stock wire in place. There are quite a few alternator builders. Mine was built by HO-Alternators and distributed through Metra as a Tsunami product. I've use Powermaster in the past as well. As the power increases so does the heat generated, if the alt body is coated, it holds in more heat. So with the 200+, keep them natural or polished only so you don't cook the bearings.