overdriven t8

I have one fixture already built, getting a new ballast and bulb sockets/holders tomorrow. What kind of par can i expect with 4x48 64 watt 6500k bulbs at 20-24 inches above substrate? Also i have a 2 bulb t5ho 36" 39 watt 5000k. Would it be in my best interest to include that in fixture in to the new system? It will give me a combined wattage of 334 or 2.7 watts per gallon on a 125g long.