http://www.the12volt.com/installbay/forum_posts.asp?TID=73496&PN=1

Thanks for the link! So once thats done.....then i can run the second battery to alternator right?

thats a long post on what the big 3 is. could have summed it up in a paragraph.

i think i should also get a higher power alternator.......dont think my 90 accord stock alternator could handle them

how much power are you going to be running. I have a 1992 Accord with stock altenator and i have a kicker zx1500.1(1700+ watts) and a mtx 2300xw (at 4 ohms stereo around 200x2), so thats around 2100 watts. I have a yellow top optima under the hood and another yellow top in my trunk and i have done the big 3 (in 4 guage for now) and i'm fine. I get very very minor dimming and thats because i don't think my second battery is grounded good.

Now what do you guys think about grounding the rear battery in the back as opposed to running the ground between the two batteries?

Becasue I have done the big 3, and have a red top under my hood. But with impending addition of 0 gauge power wire and a USAmps MD1D(with a PGti600.2). I am thinking about adding a second red top batery to my car.

From what I've read, a typical car's chassis is the equivalent of 2g to 4g wire, so it would help you out, but you're not running *that* much power.