When you make more power, you need more fuel. In a standard normally aspirated car, the stock fuel pump delivers just enough, plus a little extra. As the pump ages, it may no longer be able to deliver its full rated capacity. When you add a supercharger, you need more fuel at a higher pressure. Odds are that your stock pump will not meet this demand. The result is a dangerously lean running condition. There are plenty of generic pumps out there, but only the JR High Output Fuel Pump has been specified to deliver the correct amount of fuel. The JR pump is a direct in tank replacement. If you are installing a supercharger, we highly suggest replacing your stock fuel pump at the same time.