I still think it will be fine, as long as it's true 4ga wire. The theoretical max current draw, in reference to the fusing on both of the amps combined, will be ~100a total. Most 4ga wire can handle between 125a and 150a of current. If the dblink is true 4ga (you'll have to do research to find out), and made of OFC instead of CCA, you will be fine.So db link must be out ? I was looking at a zx550.2 and db link combo on ebay.