fuel pump wire with high/low voltage circuit
Jan 23, 2017, 12:35 PM
#226
I think you may experience a minimal performance increase because the relay is on the firewall so you still have the stock wire going from the firewall to the pump. it will be interesting to see how well it works though.
Jan 23, 2017, 01:47 PM
#227
EvoM Community Team Leader
For an Evo 8 the wire comes out of relay 2 as Brown, then it goes into connector C-123, it then comes out as red/white into relay 3. It comes out of Relay 3 as red back into C-123, then out again as white which it stays through C-113 and D-33 all the way to the pump.
May 23, 2017, 10:33 PM
#230
EvoM Guru
iTrader: (1)
Originally Posted by Evolution Z
anyone ever try this on cz4a platform?
Aug 17, 2017, 01:52 PM
#231
Yes, it would work fine for an Evo 10 as well. The wiring diagram is so simple that I didn't bother posting it. To summarize though, its very similar to a traditional hardwire but with two differences:
1) Put a pressure switch inline with the wire coming off the battery. I recommend the pressure switch sold by SpoolinUp.com.
2) Splice into factory power near the pump power plug rather than cutting the wiring.
Also, don't forget to splice in some additional grounding. That's just as important as the power.
The other question that goes for a standard hardwire or this hardwire is where to run the wiring. I think a lot of people just run it under the car. This is definitely super easy, but be sure to protect the wiring with some kind of loom or sheath.
I never had an issue with pressure spikes on the stock FPR for any reasonable setting on the low/full voltage table. Note that I did substantially alter the low/full voltage table. I think it needs to be done even for something like a W255 upgrade.
1) Put a pressure switch inline with the wire coming off the battery. I recommend the pressure switch sold by SpoolinUp.com.
2) Splice into factory power near the pump power plug rather than cutting the wiring.
Also, don't forget to splice in some additional grounding. That's just as important as the power.
The other question that goes for a standard hardwire or this hardwire is where to run the wiring. I think a lot of people just run it under the car. This is definitely super easy, but be sure to protect the wiring with some kind of loom or sheath.
I never had an issue with pressure spikes on the stock FPR for any reasonable setting on the low/full voltage table. Note that I did substantially alter the low/full voltage table. I think it needs to be done even for something like a W255 upgrade.
....from this pump hardwire write up: http://lancerregister.com/showthread.php?t=459924
Instead of the fuse coming from the battery (picture below) I use the pressure switch and instead of where it says cut the power wire going to pump I will splice it and connect to it. Other than that I can just follow the write up?
Thanks
Aug 17, 2017, 02:37 PM
#232
EvoM Guru
iTrader: (1)
Sort of, you have 30 and 87 reversed. 86 and 87 get spliced into the stock fuel pump power wire. 30 gets power from hobbs switch, which gets power from the battery. I would put the fuse in between the battery and hobbs switch.
Aug 18, 2017, 08:25 AM
#233
- The diagram indicates taking 12 V power from a fuel pump relay to go to terminal 86. Taking power from a "fuel pump relay" is a bit of a vague statement because there are three relays associated with fuel pump operation, and they all have different conditions when they are active. I would take it from "ON" ignition power or from "ACC" power from the fuse panel under the dash. It would also be fine to take directly from the battery. Battery would be easy because the automotive relay and Hobbs switch are easiest to install in the engine compartment.
- The Hobbs switch should be connected to terminal 85. Terminal 86 should go to ground. This is the switching signal circuit. Its necessary to use terminal 85 for the positive terminal because some relays may have a flyback diode, and if 85 and 86 are reversed, then it creates a short circuit.
- I want to clarify that "splice" into the fuel pump power wire coming off terminal 87 means to merge this additional power wire with the OEM fuel pump power wire. Do not cut the OEM fuel pump power wire. This new power source does not replace. Instead, it augments. Perform this merge in the factory wire harness at the point where the OEM harness connects to the fuel pump carrier (the white thing that holds the fuel pump). If you use a crimp splice, be sure that its up to the job of carrying up to 20 A of power. Otherwise, do a solder splice.
Aug 18, 2017, 03:11 PM
#234
EvoM Guru
iTrader: (1)
I'll add a few more details.
- The diagram indicates taking 12 V power from a fuel pump relay to go to terminal 86. Taking power from a "fuel pump relay" is a bit of a vague statement because there are three relays associated with fuel pump operation, and they all have different conditions when they are active. I would take it from "ON" ignition power or from "ACC" power from the fuse panel under the dash. It would also be fine to take directly from the battery. Battery would be easy because the automotive relay and Hobbs switch are easiest to install in the engine compartment.
- The Hobbs switch should be connected to terminal 85. Terminal 86 should go to ground. This is the switching signal circuit. Its necessary to use terminal 85 for the positive terminal because some relays may have a flyback diode, and if 85 and 86 are reversed, then it creates a short circuit.
- I want to clarify that "splice" into the fuel pump power wire coming off terminal 87 means to merge this additional power wire with the OEM fuel pump power wire. Do not cut the OEM fuel pump power wire. This new power source does not replace. Instead, it augments. Perform this merge in the factory wire harness at the point where the OEM harness connects to the fuel pump carrier (the white thing that holds the fuel pump). If you use a crimp splice, be sure that its up to the job of carrying up to 20 A of power. Otherwise, do a solder splice.
- The diagram indicates taking 12 V power from a fuel pump relay to go to terminal 86. Taking power from a "fuel pump relay" is a bit of a vague statement because there are three relays associated with fuel pump operation, and they all have different conditions when they are active. I would take it from "ON" ignition power or from "ACC" power from the fuse panel under the dash. It would also be fine to take directly from the battery. Battery would be easy because the automotive relay and Hobbs switch are easiest to install in the engine compartment.
- The Hobbs switch should be connected to terminal 85. Terminal 86 should go to ground. This is the switching signal circuit. Its necessary to use terminal 85 for the positive terminal because some relays may have a flyback diode, and if 85 and 86 are reversed, then it creates a short circuit.
- I want to clarify that "splice" into the fuel pump power wire coming off terminal 87 means to merge this additional power wire with the OEM fuel pump power wire. Do not cut the OEM fuel pump power wire. This new power source does not replace. Instead, it augments. Perform this merge in the factory wire harness at the point where the OEM harness connects to the fuel pump carrier (the white thing that holds the fuel pump). If you use a crimp splice, be sure that its up to the job of carrying up to 20 A of power. Otherwise, do a solder splice.
I also have it set up to where the hobbs switch controls the relay ground. My battery is in the trunk, so that means I only have one wire going to the front of the car.
Jan 10, 2018, 07:38 AM
#236
EvoM Guru
iTrader: (1)
Yup, standalones are nice lol.
I actually have my car wired so that the stock hi voltage relay triggers the "supplemental" power relay. It ended up being way more complicated than the hobbs switch.
I actually have my car wired so that the stock hi voltage relay triggers the "supplemental" power relay. It ended up being way more complicated than the hobbs switch.
Jan 11, 2018, 04:19 PM
#238
I've just been looking at cable to do this, and the best I've found is to actually buy an amp wiring kit, which has the right lengths of cable in them and are cheaper than just buying the cable on its own. They have 8 gauge cable in them though, but I would guess that would be fine.
Jan 12, 2018, 06:43 AM
#239
EvoM Guru
iTrader: (1)
You just buy STM's rewire kit, and use it appropriately for this set up.
Jan 18, 2018, 03:43 PM
#240
I've got an STM kit coming.
I've been looking at my ecu wiring for fitting my Link ecu and I see pin 39 is for Fuel pump speed, which seems to be the same as the Evo 8. Does anyone know how this pin works and why we couldn't use it for triggering full power to the pump?
I've been looking at my ecu wiring for fitting my Link ecu and I see pin 39 is for Fuel pump speed, which seems to be the same as the Evo 8. Does anyone know how this pin works and why we couldn't use it for triggering full power to the pump?
