Dinan High Flow Cold Air Intake Systems develop horsepower and torque gains by improving the engine's intake air flow. The aggressive system design provides a less restrictive intake air flow than the stock system for greater engine efficiency and the lowest possible intake air temperatures.The High Flow Cold Air Intake Systems replace the factory air box with a large, free flow performance filter and aluminum intake pipe. The filter is relocated to a separate compartment behind the front bumper and below the headlights in order to insulate it from engine compartment heat and maximize exposure to cooler outside air. The filter to air-flow-meter pipe is designed to minimize air turbulence and maximize efficiency. A Stage 2 version of the Dinan Performance Engine Software is required in order to optimize the fuel mixture and ignition timing for maximum power gains. The High Flow Cold Air Intake System is 50 state emissions legal**540 Performance Data (9/98-2003 production) Peak Horsepower Gain from Intake…...13 bhp @ 5700 rpm Peak Torque Gain from Intake…..........12 lb/ft @ 5700 rpm-Dinan Throttle BodyDinan's High Flow Throttle Body for 9/98 and later 540 models improves intake air flow for additional horsepower and torque gains. The internal diameter of the stock 540 throttle body is increased by 3 mm, for an 8% increase in air flow area. The resulting increase in air flow provides more horsepower and torque throughout the rpm range, with noticeably quicker throttle response. Fully matched Stage 3 Engine Software and the Cold Air Intake System are required with the Throttle Body. 50 State Emissions Legal**.540 Performance Data (9/98-2003 production) Peak Horsepower Gain.......................... 8 bhp @ 5500 rpm Peak Torque Gain ................................ 8 lb/ft @ 5500 rpm-Dinan High Flow Air Mass MeterDinan's High Flow Air Mass Meter for the 540 compliments the Cold Air Intake System by further enhancing the intake tract for increased power and quicker throttle response. The Dinan Air Mass Meter Housing features a larger internal diameter and is manufactured from aluminum, as compared to the smaller plastic stock unit. The Air Mass Meter is designed to accommodate the stock electronics and comes with all of the components necessary for a clean and simple installation. Stage 4 Engine Software provides the proper engine management tuning for optimum performance.