my car runs at 13.8 volts with the big three and stock alternator with the relay isolater, thats .4 increase from stock wiring

 

OK well I wired up my batteries and everything works sol I did it right, woohoo. I noticed that I am running at about 100 RPM's so need to adjust it, or it might just be because it hadnt ran for a week and a half and it was cold out, hmmm?

My next question is ready to be asked though. I was thinking about which battery I was hooking my amps too and it got me pondering. Should I hook them up to the battery that is directly connected to my car, or the secondary battery? I mean this could be good because then when I am at a show I could run everything on the main battery and then when I goto start I dont have to worry because the second battery would kick in to start my car....am I thinking in the right direction here or am I just dreaming?

 

With a relay, either will technically work. I guess its probably a little better to run the amps of whichever battery is closer, but then you have to make sure everything else is on that battery (head unit, eq, anything else that comes on when your key is in the accy. position), if your goal is always being able to start your car.

For your purpose, it makes sense to run all audio off of the main battery, and then just use the second battery to 'jump start' the car, if you run the main one down. This way, your second battery is free from all loads that could be present while running your stereo.

How is the relay wired? Specifically, where does it get its open / close signal voltage from?

Toby

 

Thanks, I was thinking of doing the circuit that way but wasnt 100% sure. I was thinking of running the signal voltage for the relay off a switch that will be in my glove box because I am making my glove box where all my control's and everything are. What do you think about that?

THANKS again

 

The switch can be almost anywhere. What I'd do, is run an ign power lead (one that is hot when the key is on) to the switch, and then on to the relay. Then, you leave the switch 'on' except when you want to play the stereo for long periods of time. The relay will open every time you shut the car off, which will keep the batteries from running each other down. Just make sure you flip the switch 'off' when you are playing parked, or all your work will be for nothing.

Toby

 

well after upgrading all my wiring,I finally hooked up my alternator and found out it is pulling a MAX OUTPUT of 192 AMPS.... woot woot

 

how did you measure that?

 

I took my car to discount and had them hook there mobile machine to it