Battery setup help needed

[swift 501]

As of right now I have a Mechman 270 and two optima red tops under the hood in stock locations. Big 3 done also. I am dropping into 11's on full tilt at idle and mid 12's while driving.

I was originally going to replace both red tops up front with the two d3400's which I think would be fine for my power (3600watts roughly) but was wondering should I leave the Redtops up front and put the d3400's in the rear and run wire directly from my alt to those that way they don't pull from the red tops and they are dedicated to the system? Is this a option or should I just stay with my original plan running both up front.

Thanks

[swift 501]

ttt

[ncacoates 104]

Something is wrong if its dropping that bad. I'd suspect a bad alternator or bad grounds. I have roughly twice the power on 160ah of battery bank and an xp250 with little drop. I maintain 13+ most the time full tilt.

[swift 501]

Something is wrong if its dropping that bad. I'd suspect a bad alternator or bad grounds. I have roughly twice the power on 160ah of battery bank and an xp250 with little drop. I maintain 13+ most the time full tilt.

It is strange, I hope the alt is good, SOB was expensive.

I only have a 250amp fuse up near the battery. Based on my volt meter which the power goes into the amp + with the main power wire, and it is grounded up front at a factory ground location. I would think that its reading accurately. I calibrated it with a dmm at idle.

At the 11.2 Volts that I have seen, 2800 watts should have popped that fuse if I am figuring correctly. I have a 3k and a 600 watt amp. I must be leaving alot on the table?? The box the alt came in said it tested at 178amps at idle and 279 at full output. My Optima's are 3 years old and rest at 12.5 with the truck off. When the stock alt was in and the SAZ1500 the Volts would hit low 12's high 11's at idle.

What ground would be bad? The amp where the voltage is reading?

[Nathan@XSPower 47]

If you are running two Group 34 red tops, then I would get them checked. 3600 watts with a 270amp alternator should not be dropping below mid 12V range at the most with the vehicle running. Lets say you are only getting 180amps at idle. That would put you with about a 230amp pull over what your alternator is putting out at idle. 230amps divided between the batteries is only 115amps of pull each battery. This is considering you are getting all of the power out of your amps, and you are not seeing any more than 180amp from the alternator.

I would check the batteries and all of your wiring. 2 D3400 should work fine with that alt on 3600watts.