Take a look at what the 68 & 69 BB darts are doing in stock eliminator. A cast iron head that has some tricks but very close to stock. A relatively stock profile camshaft(ramp and duration are adjustable) that puts these cars into mid 10's. That head and motor are working with lift below .500. As mentioned, a Stealth head with a cam under .525 and the right converter and gear will bring you down to 11.0 and easily into the 10's. Nothing exotic, just parts working together.