For Nissan 240SX Fuel Rail Kit (Blue)+Intake Manifold+70mm Throttle Body (Black) - S13 SR20DET Improves Approximately 30% Air Flow and Eliminates Secondary Butterfies; thus, is Good for Significant Horsepower Increase and Top-End Power Gain Supplies Additional Fuel Needed for High Boost/ Performance Engines 5/8" Fuel Bore for Larger Fuel Flow; Pre-Taped Ends Allows -6 And -8 Fittings Compatible with Stock Fuel Pressure Regulators or Adjustable Fuel Pressure Regulators 1/8th NTP Available For Nitrous Systems or Fuel Pressure Gauge; Fits 10.5mm - 11mm Top Feed Injectors