I have been doing some searching and reading on holley blue pumps, and I noticed that some people used a relay and fuses on their pumps. Is this necessary? Can I just wire it from the Lift pump and be done with it. Then just monitor my fuel pressure gauge...

 

You could, but it's a good idea to use a relay to make sure the holley is getting full power.

 

Any one have a wiring schematic as to how the wiring would go with a relay included?

Is the fuse really necessary...

 

There should be a picture on the back of the relay box or instructions on what prong does what. If not, let me know and I'll get you one real quick.

 

My pump was going crazy the other day... fluctuating... thought it was dying. then I realized it went away after a few minutes... I have the "dimming lights" syndrome on my fuel pump right when I start the truck up. Probably from big draw starting and grid heater. Also have crappy batteries and no relay. Eventually I will do both and it'll probably fix the problem, but either way at least it isn't actually dying.

But basically.... more voltage=more volume, I think. A relay and good wiring will guarantee you get the most.

 

I had my holley red wired up straight positive and negative first time....someone else did it It lasted about 150 miles. The holley got smoked and almost cost me a VP. Second time I wired it in with the LP (get the LP extension from Cummins) and hooked it up via a relay on the drivers firewall. Just a simple 4/5 post relay, 1 inch square. It has worked like a charm since. Only fires when the LP runs.

Roman