So, if I stroked my Dart Block 502's to 540's or higher, got a whipple intercooler, more carberator, aluminum heads, new cam and an 8-71's blower, how much HP do you think I could get and still run on super unleaded?

800-850 hp easily with those mods. Then you would start to run out of blower again. If you went with a Whipple, then you could make about 950 hp with that setup.
Eddie

Which Whipple are you talking about, the Quad Rotor?

No, a single 3.3 liter.
Eddie