Theres no need for heads if your willing to beat the car. My suggestion if you just want a 12 second timeslip, and a good basis to build the car from, some 4.10s ($300), pulleys ($100), clutch ($200), shifter ($200), Driveshaft ($250 now or so), and then finish off with some slicks ($320) and suspension (whatevers left) and you could rip of a 12, and have the car set up later for heads, cam and intake. If you want a 12 easier, then nitrous, gears and tires!