Am i looking at that wrong, or is it 13AFR at 34psi? and 12afr at 28???

 

Cool, that's the same setup that I have. I just used 1/4" fuel hose but that's basically what -4an is.

By far the easiest solution and if you have an afpr then idle should be fine. For people on E85 they could install a boost-a-pump and get more output from their 255 while solving the issue. Of course a relay and some wire is maybe $15 vs $200 for a BAP.

 

 

I've never heard of this. So are there part numbers for these relays? How much do they cost?

 

Ehhhhhh.....I so dang tired of buying relays I'm beginning not to care anymore. Green, Blue....I had bought a few of them (both types) just to have some extra on hand and now they are all crap? What a waste....

 

Any relay can fail. The problem with this one is that it can fail at 9volts. I have mine wired to battery (using a Bosch relay) and if you have an afpr then that's a permanent fix.

 

its funny , i never had any if these... I changed the relay to green just because the site said it will fail..
Are you sure it is a relay problem? How many miles do you have ?
It is interesting if you have a fairly low mileage and you experience so many failure .
I had a MAF failure in the row , and i did throw out the HKS drop in filter, and i did put the K&N instead in it. Since then and after more mileage then the HKS been in my car, i had no failure again so far.
What im saying is , maybe something cause this so many failures, not the relay itself. For me sounds more logical that, then always getting the bad relay theory.
Im not saying you are wrong or anything, but i would look into this matter with some pro or very very experienced electrician guy /car/.

Rob

 

The relays only purpose is to kick the pump from 8volts to 14 volts right? Why not use a jumper wire instead of the relay and keep the pump at 14 volts all the time? You will have to adjust your fueling in the cells before the ecm kicks the relay on. Or use an external relay like Kosmic27 stated.

 

There are alternate relays that will fit in that hole that are much higher grade. I will see if I can dig some part numbers and prices up in the next couple days.

 

Because you will burn the fuel pump out.

 

By running at 14 volts all the time like alot other cars? I thought alot of dsm and older evo guys bypass this circuit completely?

 

If the stock pump was designed to run at 9 volts most of the time, I doubt it will last that long at 14 volts. The fuel return system isn't designed to flow that much fuel (cause you won't be using it), so the pump will be running at higher pressures, and higher pressures ruin pumps.

Idle will also be messed up at the higher pressures. You will need to tune it out.

 

The problem with that logic is most of the people having these issues run a walbro 255s not stock pumps. I have installed 20 or so walbros in various cars, all of which run full voltage to them at all times. Even if the oem pump is used, I personally would rather an oem pump fail completely than the second relay not kick on when you need it most. I also dont think the return line would be a problem since some are running twin pumps through these oem lines. I have already stated that you would need to tune out the richness from the pump running higher voltage at idle and cruise.

 

Here is how the 3000gt guys do it. http://www.stealth316.com/2-fuelpumprelaybypass.htm

 

The fuel pump should be fine. This is done for a few reasons...

NVH ---this is great if you have a walboro that is of the whiney variety.
Lower flow at idle / cruise --- you don't overrun the FPR
Slightly lower energy cost --- less pumping around fluids aimlessly

A walboro is designed to run at 12v/14v, and I'm sure the factory pump is also. Reducing the voltage may prolong the life, but not significantly (probably more from a standpoint of wear on revolving parts). The only catch might be if you drive with no fuel all the time and the pump heats up more, but thats out of scope.

One alternative if you wanted to keep the factory style system would be to just wire up 2 relays in parallel. If one failed, the other would still be there as a backup. You just have to make sure you don't skip the resistor.

I hated the loud *** whine of the walboro in my 2g... and before I rewired it you could hear the power oscillate when you put on turn signals or turned up the stereo. Totally annoying and pointless.