The opening and closing of fuel injectors creates pressure pulses in the fuel rail; this can lead to unstable fuel pressure. In order to achieve a safe and consistent rail pressure, a fuel pulse damper (FPD) is often necessary. The FPD's internal diaphragm will absorb oscillating pulses and stabilize fuel pressure. This correction can be measured throughout the RPM range and can often help idle surge, especially with high flow injectors. Furthermore, a fuel pulse damper can help solve erratic lean air/fuel ratio spikes, commonly experienced as 'stumbling', that are difficult to tune out.Fuel pulse dampers can be mounted at any angle, including upside down. This product is safe for use with all fuel types including alcohol blends such as E85. Fitting Size: 8 AN ORB - Fits Radium Fuel rails with 8AN ORB provisions. Standard Operating Range: 40-70psi Standard operating range should be used on vehicles with a base fuel pressure between 40-70psi. If fuel pressure is static (does not fall or rise with manifold pressure) then no vacuum reference line is needed. If fuel pressure rises or falls lower or higher than the operating range, a vacuum line is needed. Included: Anodized and laser engraved aluminum top Anodized aluminum body with male threads, 8AN ORB Stainless steel hardware Rubber vacuum hose, 4mm ID Vacuum hose Y-fitting
