Big Turbo Software Precisely Engineered to Run 20psi of Boost on a Stock Engine. (For over 400HP you need a built engine). Upgraded Exhaust System RS4 Injectors High Pressure Fuel Pump Upgrade Upgraded intake (OEM MAF size required) Upgraded Low Pressure Fuel Pump (For over 450HP) Upgraded Rods (For over 400HP) Water Meth Kit (To Reach more than 500HP)Engineered with Strict Industry StandardsExtensively Tested Under Various Driving ConditionsOptimized Responsiveness and DrivabilityPower Delivery Perfectly Optimized Throughout the Power BandSpeed Governor RemovedRPM Limiter Increased to 7100 (With Stock Head)Ignition Timing Precisely Calibrated for Higher Octane FuelIncludes Stage 3 tune and all lower software stages.