this is an interesting topic.... if your running a 600rms amp why aren't you using a 2 gauge or even 0 gauge? you'd have a better flow. I'm running a 0 gauge to a distributor which sits 15cm from my amp and i've got 1 8 gauge going into my rockford lenght of that is only 30cm. I also have a spare set up for a second amp which i use in db drags, good ol 1501bd. But seriously your really restricting breathing of those amps even though there's ample room for air, there's no fresh air circulating the amp. Its nice though really good effort making it clean. I really didn't have a choice in mine, i couldn't bare go back to a single sub. So i have to deal with a dual and amp mounted on the back of box. If you have the factory battery, that's just ridiculous, your lights will dim, definately would need a capacitor with the system your running. That and a decent battery.