There is no such thing as a too-big battery cable. A 12 volt system can get by with a #4 cable, but it will have a lot less voltage drop with a big one, #1 or #0. On the race cars, we made our own cables out of #0 welder cable with about a thousand hair-fine strands of wire, and soldered all the connections. They would crank a 12:1 compression engine easily, and I've seen surge current of close to 1,000 amps when a high-torque starter kicked in on a hot restart.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!