what gage wire would i need to use for the altenator, if the battery is in the back.... some people say 4 some say 8 gage ???

 

2 Gauge

 

2 gage for the power wire to the altenator??? dont you think thats a little to much?

 

2 gauge. Simple little rule for battery cables, the longer the wire the thicker it needs to be.

 

Go to this site and run the calculations yourself: http://www.powerstream.com/Wire_Size.htm I checked with the following parameters:
4 AWG
12 VDC
8 foot 1-way circuit length
65 amps
Voltage drop = 0.3 ohms -- very respectable.

This gauge is probably overkill, since your alternator is unlikely to feed max current directly to the battery for any length of time.

Another thing to consider is where you're running the cable to. I run mine from the alternator back to where the battery cable attaches to the starter solenoid. This makes the run much shorter, so I can run a smaller gauge (I'm running 8 AWG).

 

i agree the battery cable should be 2 gauge... but would it be bad to run a 8 gauge for the power to the altenator, its only running 10ft or so.... or is there a 6 gauge wire???