Ron Francis Wiring, Complete Kit, MSD Atomic EFI Fuel Pump question

[Rodster]

I posted this on the Roadster side, since most all parts over there are the same over here.

Question: My engine has EFI (MSD Atomic) - the external electric fuel pump is powered/regulated by the EFI computer. (It is a PWM signal, not just "12 volts.")

In the Ron Francis wiring harness, there is a pair of wires for fuel pump.

Do I un-plug the tan wire from the RF fuse block/Main harness, and plug the EFI fuel pump wire into there? I do not want to bypass the inertia switch. I have removed the 15A fuse going to the fuel pump.

Is this correct? Any thoughts?

I suppose the "easy" way would be to just not use the RF fuel pump wires and run the MSD EFI fuel pump wires out to the back. . . .

This is what it looks like, the manual does not show this connector. . . .

014.JPG

Thanks.

[michael everson]

If you want to maintain the trip switch then you can probably just not use the power wire from the EFI. Or you could use the EFI wire to turn on the relay in the RF fuse box. Cut the short tan wire from the relay and hook up your EFI pump power to the short wire.

Mike

[Rodster]

Mike -
Thanks. I have similar replies from the Roadster guys. I will verify with a meter this weekend to be sure before doing any cutting. . .

[BobCarter]

Rodster, Mike is correct regarding clipping the tan wire and using the MSD Atomic to control the fuel pump. I have the exact setup you describe except i decided to go with a return system. Also, consider using the MSD Atomic to control the radiator fan. Im in the go cart stage and all these mods work well on my 351W.

[Rodster]

Bob - Perfect Thank you. I am also running a return fuel line. And this is confirmed. I will pull the fuse for the fuel pump. Then I will cut the wire feeding the fuel pump line, and splice the MSD fuel pump wire onto the tan wire going to the fuel pump. This should retain the inertia switch.

Thanks also about the note on the fan, and I agree this is also my approach - use the MSD to control the cooling fans. I have some beefy relays for that. I will also add a toggle switch so I can manually turn the cooling fan on.