LSJ LS4 75mm Throttle Body

The ZZPerformance LSJ LS4 Throttle Body is a performance upgrade designed to feed your supercharger with increased airflow, leading to reduced parasitic loss and improved horsepower. This throttle body measures 75mm, a significant increase from the stock 67.4mm unit, and is intended to mate with a 70.5mm stock blower opening. To achieve full potential and prevent interference, modification (porting) to the blower inlet is required. If porting the blower inlet is not planned, a throttle body adapter/spacer plate is necessary. Additionally, due to the larger inlet size of this throttle body, a compatible LS4 silicone coupler is also required. For optimal performance gains, it is recommended to port the entire inlet of the supercharger. This upgrade is best suited for vehicles that already have a full stage 3 kit, header/downpipe, dual pass endplate, and cams/valve springs installed, as it significantly enhances throttle response. PCM calibration is mandatory. The ETC area scaler in HPTuners needs adjustment from the stock value of 2950 to 3688, with many users reporting success with even higher values ranging from 3775 to 5500.