Sniper EFI and Inertia Switch wiring

[IowaBen]

I'm trying to piece together how I should merge the Sniper EFI wiring (that came with my BPE 347) with the RF Harness and my in tank fuel pump.

My "plan" is to:
1) take the inertia switch from the RF harness at put it in-line with the Sniper/Fuel pump wiring
2) pull the fuel pump fuse from the fuse block to make the RF tan elec fuel pump wire "dead"

Questions:
a) The inertia switch is part of the ground in the RF harness, I believe. Can/should I put the inertia switch inline with the ground for the fuel pump (i.e. fuel pump (-) to inertia switch to frame)? I found another post that noted putting the switch in line with the blue wire (that goes to the fuel pump (+)). Does it matter? Is one preferred?

b) If I do pull the fuse as noted in step 2, is there more to it than that to kill the tan wire? Do I need to do something with either of the wires that were connected to the inertia switch?

I appreciate any input.

Thanks!
Ben

[skidd]

Question a: That's how I wired my inertia switch. The switch is in my trunk in fact. It opens up the "ground" side of the pump. I actually glued a small cap to the switch part, so I can even pop the trunk, and manually trigger it as an added "don't take my car" security measure.
I'm not really sure if one is preferred over the other though. I did it out of simplicity of the wiring in my car, given where I wanted to locate everything. I also found that a variety of OEMs did it one way or the other. I don't recall which wiring diagrams I had found at the time of my research. Some did ground, others did positive.

[FF33rod]

Also have a Sniper
I put the inertia switch in line with the ground for the fuel pump relay. This is low current compared to the high current the pump needs. I had no idea what the rating of the inertia switch was so just played it safe.

Steve

[Norm B]

My inertia switch is wired the same as it was on the Mustang I took it out of, it interrupts the positive feed to the fuel pump. I have been rewiring the system for the Sniper and removed the fuel pump relay from it and kept the one in my fuse box. I used the small dark blue wire that runs from the Sniper unit to their fuel pump relay to run the ground circuit on the fuel pump relay in my chassis harness. I put a switch in between the Sniper and the relay so I can shut the fuel pump off for service and safety reasons.

The trouble I had was finding a circuit that was hot in run and/or start to power the Sniper unit. The only circuit I could find was the coil feed and the Sniper instructions are pretty clear about not using that. Ended up repurposing the Sniper fuel pump relay to provide battery power to the required circuit with the coil circuit acting as the positive trigger feed.

Norm

[D Stand]

(1) The sniper wiring diagram is not very clear. They state that there is a blue wire for fuel pump + and it is pre-wired to a relay. Taking the harness loom off I found a smaller blue wire from the relay to the 7 pin connecter to the sniper. This is the - trigger to the coil of the fuel pump relay and not documented. I broke the small blue and looped it through the FFR inertia switch. The large blue wire is wired to the contact side of the relay which is fed by the main + via the 40 amp fuse.

(2) I left the tan wire and shrink tubed it off at the fuel tank. Never now when you might need a spare wire to the trunk area.