Two ways, RPM or boost. For a 4X4 truck RPM is not a practical way to go. So that leaves boost. For that you need a strong block, especially the lower end. Then all forged internals. Any time you are running boost, the exhaust volume is increased so "nitrous" heads or installing larger exhaust valves and increasing port cross sectional area will help. Definately so on superchargers. Turbos need unrestricted exhaust to keep cylinder side of the exhaust valve pressure low. Your turbo pressure ratio should be 1:1.
