Big 3 4 Gauge Wire

i have my old flea market supposedly 4 gauge but fits 9 gauge connectors, would this be big enough for the final ground. I would have enough left over of the good stuff if i switch my amp around.

 

ok, i'm going to switch my amp around anyways, that wire is too long will be more efficient if it's shorter. I'll use that leftover peice of the real 4 gauge, it's from a bassworx kit. The alternator charging wire i put is the same flea market crap but i do have the original wire of the car also, so there is two wires, is this enough? The original from the car looks like 8 gauge.

 

My sub should be here tommorow. Ok i'll leave it for now but will get another kit and do it properly. It really is crappy wire...never again will i enter a flea market lol.