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Best way to wire fuel pump relay

16K views 15 replies 6 participants last post by  michael a  
#1 ·
Need to wire the fuel pump relay for the 454 swap,where is the best place to wire the relay into? Anybody have a pic of linkage hooked up with the 4 speed with overdrive .
 
#2 ·
Fuel pump relay

For my 1984 xfire to carb conversion I made a new circuit, bypassing the factory oil pressure/fuel pump set up. I ran a 12 gauge wire from the relay(separate new relay) all the way back to the sending unit at the tank, clipped the original power wire to the fuel pump and wired in the new 12 gauge wire. I used 12 volt power from the back of the positive terminal on the alternator for my power "in" to the relay and I spliced in a 12 gauge wire to the power wire going to the distributor as a "trigger" wire for the relay and I used a circuit breaker on the 12 volts coming from the alternator and I used a fuse for the wire going back to the fuel pump. For safety sake I also wired in a Ford inertia switch so that in the event of a crash the fuel pump will shut off. This is a nice clean circuit so I do not have to worry about using an old circuit and the oil pressure switch to control the fuel pump operation. I also have a manual on/off switch under the hood so I can turn the fuel pump on and off for whatever reason and doubles as a anti-theft device. For the relay I used a heavy duty cole-hersee constant duty marine solenoid instead of the standard plastic type relay. This is overkill for sure but it works great. You can email me at docwilcar@yahoo.com if you have questions. Good luck.
 
#3 ·
Need to wire the fuel pump relay for the 454 swap,where is the best place to wire the relay into?
If you haven't butchered the wiring up you still have everything needed in place.
All you need is to run the green/white wire at pump relay to a key on (Ign ) source.
If you have any of the stock wiring under hood then any of the pink/black wires are hot ; key on

If you have gutted wiring then all you need is relay output connected to the old pump feed wire ( heavy red ) than runs to pump through stock fuse
 
#10 ·
Need simple sketch on how to wire fuel pump , gutted wiring in engine bay . Found two red wires on pass side floor also red,green,white and another red wire going under door seal . Hooked up 12 volts to fuse panel tonight to see if it would fire up. Any help would really be nice ,and thank's before hand.
 
#11 ·
Need simple sketch on how to wire fuel pump , gutted wiring in engine bay ..
How do you want to do it?
Pump run; key on or a manual pump switch?
Do you still have the pump relay?


Found two red wires on pass side floor also red,green,white and another red wire going under door seal . .
Going to need a lot more detail to identify random wires like where they originate from
 
#13 ·
having no idea what wiring you have in car
at most basic need
a fused wire from batt to fuel pump running through a relay that gets it's control circuit power from the switched side of Ign switch

Same as what was in your car except terminal C on relay would now come from key (and no oil pressure switch )



Image
 
#15 ·
You need a relay because pump draws too much current to run direct from Ign switch.
Whatever you use to operate the relay determines how pump runs so in above case so long as ign on ; pump will run

I installed the factory OP switch on my carb 383 so I have back up should relay fail.
When that engine goes in my race car I will have the relay operated by a push button switch as carb prime only and then pump running from the OP switch which closes at cranking speed (4 psi ).
NB;
you only get 2 sec prime if relay is operated by the computer