so, just how many amps do these car amplifiers draw then, i mean through its power cables.
i point blank refuse to belive power cable that thick is needed.
if a starter motor will work fine on cable half its size i cant see a stereo system needing more
Interesting point.....
As stated length of cable plays a big part.....
When selecting power cable for an audio install you need to consider two different things, one is safety, one is voltage drop....
0AWG at 16' will support massive ampage safely, but voltage wise you wouldn't want to exceed 150amps....once you exceed 150amps voltage will suffer....
If entering audio competition where installation is considered, all these factors are taken into consideration and are marked accordingly, for example if your using a 5mtr length of 4AWG, it should be fused at no more than 80amps....if it is, then points will be lost....
Don't confuse safety with efficiency, 0AWG tends to be used because its relatively easy to work with, but in some cases its still not big enough....
here's a link to an extreme car being built by dumdum, this car is for pure SPL and is only using one battery, (but its a big one), this is serious amounts of cabling,
dumdum and his buzz bars .....20,000watts rms!!!!!!
Just for information, if your install will exceed a max draw of around 275amps, i would suggest you opt for direct battery earthing, (a cars chassis will support around 275amps to 300amps on the return path then resistance becomes an issue and voltage will suffer).....
So to OP; If your draw exceeds 150amps at 16', congrats mate, you need two runs of 0AWG, or upgrade to a single run of 2/0AWG....
If your max draw exceeds 250amps, I'd go 2/0AWG power cable and 2/0AWG earth cable from boot to battery.....