STG1 Fuel System Upgrade

The Visconti Tuning STG1 Fuel System Upgrade is engineered to significantly increase fuel delivery for high-horsepower B58 engine applications. This kit is designed for BMW G20 M340 and G42 M240 models that require enhanced low-pressure fuel supply to effectively support upgraded turbochargers, port injection systems, and higher concentrations of ethanol fuel blends. This system incorporates a second in-tank fuel pump, utilizing Walbro 525 technology, while maintaining the factory's plumbing and fuel routing. This design ensures stable fuel pressure, even under extreme high-horsepower conditions. Extensive testing revealed that the factory low-pressure fuel pump begins to experience significant pressure drops around 750 WHP, a situation exacerbated by higher ethanol blends. By adding this second pump, the system provides the necessary additional fuel volume to maintain optimal fuel pressure and support elevated power levels. Key components included in this upgrade are a Walbro 525 fuel pump, Visconti fuel pump bracket, 3/8 quick connect fitting, replacement in-tank fuel line, sealed wire pass-through, Holley fuel mat, and an NJ style zip tie. Advantages over alternative solutions include keeping the secondary fuel pump within the fuel tank, eliminating the need for additional fuel lines in the engine bay, and ensuring proper fuel pickup even when fuel levels are low. For wiring, if not using the ReFlex Sequential Port Injection Kit, activation of the fuel pump relay will require a non-ReFlex harness and a Hobbs switch (sold separately). It is important to note that certain products may be intended for off-road or track/competition use only and not for public street use, and buyers are responsible for ensuring compliance with all applicable laws regarding emissions and vehicle modifications.