Battery relocation wiring question

[toledo240]

is it that important to run 2- gauge wire for the positive wire or will i be fine with 4 gauge wire?would you guys replace the whole positive wire to the starter or would you guys make some connection with another wire to the battery?

[Rex]

I'd run the biggest you can, as the length will offer some voltage resistance. Can you fit (car/budget) 0 gauge?

Also, run the full length as a single piece. As with anything "connections" are always your weak link, and could be a problem later. Not to mention the existing wire is a little old.