I am installing a new amp an was wondergin what size power wire I shold use. The amp is 1200 pwak watts and 500rms watts. I have a 4 gague from my old car, but was wondering if I coudl get by with a smaller wire like 6 or 8?

 

The 4 gauge will be fine. If you wanted to buy new wiring get 2 or 0 gauge for better flow and less resistance.