heads, s/c or turbo??

Its your car, do what you want. Heads will be the cheapest but have the least power gains. Turbo and a S/C will give you the most power, but then agian they will cost at least double what a set of nice new heads cost. Also, with a S/C or turbo you'd have to get it tuned before doing anything else, and probably upgrade your fuel and ignition where you wouldnt HAVE to with new heads.