That is kind of a tough one that has always been a touchy subject of light arrows vs. heavy arrows. I would say with your setup right now you would be lucky to shoot 265fps. With a lighter arrow you would increase your speed but might not hit a animal as hard as the heavy arrows would, that's where all the controversy comes in wether you want more feet per second or more foot pounds. I'ts all up to you. If your bow is really quiet shooting then I would'nt worry about arrow speed and deer jumping the string. Just hit em hard!