The timing and duration that your engines valves lift is critical to performance and the characteristics of the truck. Adjusting these with a custom camshaft can have drastic effects on power, turbo spool up, and torque produced. The stock camshaft was designed for low power levels with a small turbo, and short fuel injection times. When these are raised, then you start pushing your truck out of the efficiency parameters that the stock cam was designed to handle. Freeing up this extra horsepower is as simple as swapping in a camshaft designed to fit your specific needs.