what are some different ways to wire a second battery in the back, ive gotten a couple different answers one costing like 500$ buying some isolator,a bat and then another part. and i dont wanna spend 500$ for that just want the best but cheapest way, dont want dimming and somethig to power about 1200 rms thanks

 

There is only one way to wire it up and that is in parallel with your current battery. Now that we have cleared that up... all that is left is making the additional battery a non-safety issue. Simply adding a battery doesn't make anything unsafe it just provides opportunities for disaster that didn't exist before. Little things like fuses and battery tie downs I think are mandatory. The isolator might be a good idea too I do not think it is mandatory though.

so is cheap going to override safety?

 

never said anything about cheapin out on safety. just want the cheapest way to add the second batt.

 

u dont need an isolator. you need two identical batteries.

 

yuli im not getting 2 identical batteries, dont have money for that. im most likely getting a deka battery for the back and keeping stock acdelco bat for the front

 

Yup.. or if you do go the isolator route, don't get a diode type isolator. Just buy a 300Amp relay and wire to trigger off Ignition or accessory.

 

For the relay look for it at farm suppliers. the automotive relay isolators are just 300A farm relays marked up about 300%

 

okay, so id be going with the relay isolator, i just run 0gauge from the pos and neg, on the front battery to the rear battery, and then where do i put a fuse(and how) and then where do i put the relay. also then id ground the battery, then run my amp power and such to the rear bat?

 

Fuses at BOTH batteries as close to the battery terminals as possible. Relay can be anyhwere.. usually much easier to place under the hood, near the original battery..