Elect relay and EFI fuel pump questions

[bax]

I am wanting to hook up a relay for the fuel pump. I have the parts but I am a bit unsure how to do this. My holley commander 950 has a wire that runs the pump. My new harness also has a wire that runs the pump. My holley instructions tell me to use a relay. Both wires will become hot when the key is on. The holley wire is small. the harness wire is bigger. If I use the holley wire for an exciter / signal wire is there a chance of backfeeding to much power into the ecu? Am I making this harder than it needs to be? It sounds kind of silly to interupt the harness wire but the pump needs to be controlled by the ecu. I should be able to hook it all up and use the harness wire for the power to run the pump ( hot with the key on) The relay should allow the ecu to signal the pump to run. Correct? Do I need an inline fuse on the signal wire? if so how big of fuse?

Thanks
Bax

 

[bax]

No worries. Nick helped me out.

Thanks
Bax

 

[Madgyver]

Tell us what did you do.....

 

[bax]

I installed the relay using the ecu wire as a signal / exciter wire. I cut the harness wire and used both ends for power in and out of the relay. No fuse is needed because the harness wire is on it's own fuse. Nick Has been really great helping me out when I need it. I got the rear of the truck all wired up. Now it's time for the engine bay.

Bax

 

[patr1ck]

Which commander 950 are you using? The 400 cfm or the 670 cfm. Also, which engine are you running? I am interested in doing this upgrade too, but im confused on which commander to buy for a stock 302. Thanks

 

[bax]

I am using the 1000 cfm unit. it's the universal kit for a MPFI.
I am running a 400.