You shouldn't need any big 3 for that amp your electrical is in good shape, it really doesn't pull that much power. Yes, run 4 gauge. I also had to switch from 8 to 4 when I installed the amp. Mimes run under the carpet, so I taped the 4 to the end of the 8, and pulled it through. This made it easy to run the new wire.Dang, ok. I didn't really want to wire up another power cable lol, the car is a pain in the butt to run the cable ty for the info I work at a parts store so I can get a discount on an AGM battery, and my alternator is pretty new also.
Current is PULLED BY the amp, not PUSHED TO the amp. If the current going to the amp is excessively high, it is due to an issue with the amp itself overdrawing, meaning your amp is already broken or you wired it too low. The fuse in the power wire will open the circuit if the amp pulls too much current or if the power wire gets shorted to prevent the wire from heating up and causing a fire. Built in fuses primarily protect the amp from wiring mistakes. I can't think of any scenario where a properly wired/loaded/functioning amp will suddenly pull an excessive amount of current and having a fuse in your power wire will protect it.I don't mean to take over this thread, but I've seen people say this often.
When doing runs between batteries and alt to battery, I understand this because you're protecting the wire, not the equipment. But when you're fusing specifically for an amp, isn't that to protect the equipment (the amp)? So wouldn't you just use the recommendation of the manufacturer or whatever the math equals to as far as wattage output?
Not trying to say your wrong, please don't take it that way, just curious