Stage 1- A great running race engine has to breathe. We start by modifying the intake and exhaust ports to speed up air flow. The valve seats are the next area we modify using a 5 angle radius design. We recommend installing a Vertex or CP hi-compression piston. Improved throttle repose and a nice increase across the rpm range can be expected. Pump gas friendly. Send us your cylinder head with valves and camshaft(s) left in.