anyone know how to hook up an additional 12V fuel pump wire?

 

What for?

 

There is a theory that the voltage drops from the battery to the fuel pump. This is due to the resitence from the small wires and all the harness transfers, in the path to the FP. Many have found that by running a larger wire directly from the battery allows for a true 12v and even closer to the 14.1 volts the battery/system is putting out. This forces the FP to be able to push more fuel. Effectly giving you a little more headroom.

The downside is that you may wear out the pump early. I know of a couple people who used this method when running 150 - 175 shot NOS on last gen f-bodies. It was a triggered relay that activated with the nos to provide more fuel to the injectors. Increase Fuel Pressure and increase flow rate of the f-body injectors.

"In theory", of course.

 

On my eclipse I ran one straight from the battery to my fuel pump & used the original one for the relay. It worked. Dunno about the Evo but it should work the same. When the battery is fully charged you will be running actually more like 13V-14V.

 

I thought it was the other way around that your fuel pump will last longer

 

black or red wires? What part do you connect it to on the fuel pump?

 

the Evo ECU adjust the voltage based on load or something. its a dual stage pump. Under higher demand it ups the voltage eliminating the need for the rewire like in the DSM's. I know what your saying i have the same done in my 2g GST

 

ill be running a standalone so I guess I need to wire it up?

 

IIRC, new red wire from battery (+) to a new relay from Radio Shack or something. Move the stock red wire from the (+) terminal of the fuel pump to your new relay. New red wire from the relay to the (+) terminal to the fuel pump. Ground stays the same or you can make the ground wire bigger.

 

what is IIRC?

 

IIRC = If I Recall Correctly

 

bookmarked

 

Here's the info from RRE's website of the wiring schematic for the Evo.

http://www.roadraceengineering.com/e...elpumpinfo.htm

 

So basically they've already solved the problem and there is no need for the extra time wiring.

 

No that's to show you how the car controls the single fuel pump. At low load and cruising situations the pump is being fed approximately 10 volts and at higher loads and demand the pump gets full voltage.