Fuel Pump Improvements
Jerry Mueller
Summary of Mods to Stock pump to improve capacity
These changes should take a healthy stock pump from around 55 PSI WOT to 60 - 65 PSI WOT which is sufficient for the low 12's with stock injectors.

1. Shim high pressure relief spring on fuel pump. Red uses about a 3/8 inch length of 12 guage solid copper wire cut at an angle on one end. This is jammed into the relief spring and a nylon tie wrap goes around the pump and wire to secure it.
2. Cut off fuel line neck down where it went into pulsator.
3. Eliminate pulsator by attaching pump with high pressure fuel line double clamped at the pump and fuel line.
4. Bring a large (10 guage) wire from the battery to the pump, use the stock pump 12v source as the switch line for the relay.

Buick Intank Grounding Problem
The original design relies on crimp/weld around fuel return line to carry the ground for both the in tank fuel pump and the fuel level sender. Return line gets loose and arcing occurs where it passes through the tank mounting plate. Easy fix is to drill right thru the existing welded-on ground tab on top of themounting plate. Use a screw with NyLock nut to secure a crimp on ring terminal inside the tank. The original fuel pump ground wire, which is tack-welded onto the bottom of the return line is crimped in this ring terminal along with a ground wire running right to the pump. Before you drill the hole, make sure thenut will clear the fuel inlet tube as it's pretty close. 

            Fuel                 Vent

                 \   Return  /
                   \    |    /
                     |  |  |
                     |  |  |
                  ---|--|--|---
                 /   |  |  |   \
                /    |  |  |    \
               /     |  |  |     \
              /      |  |  |      \
             |       |  |  |       |
             |       |  |  |       |
             |                     |         <----- top of mounting plate 
             | | \ [] (^) / \ [] |_| / \ \ \\ / \ \ \\ ----\---------- \\ \ \\ \ \\ welded on pump & tank level ground tab. passthru connector drill thru original ground terminal ### <--- nylock nut ___ <--- washer --------\ fuel return line original \ --------------------------- ground _ _ | ______ ____________|_____________ _______ ______ ____________|_____________ _______ | \ \\connector for fp +12v crimp on -> O==\-----\   |  \             \\  & Tank Level



      Ring Terminal         \     \ |   \- Arcing here



                              \     |



                               |    | \



                               |    |   \



                               |    |     \



                               |    |       \



                       |       |    |         \



              Screw -> |       |    |           \



                      ---      |    |             \ __ <--- new fuel pump | | ground | | | | | | | | | | | | | | | | | | | | original fp ground ---> |    |



                                \   |



                                  \ |



                                    --------   <-- fp mount ring


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