2002 USDM WRX Gas tank and 05-07 STi Fuel Sender + Surge Box
Finally got this bad boy in, and can make an official mod post about it.
Dropped the 06 Impreza tank and more or less just swapped over the piping I had already figured out for that tank. You can find all of that in my old gas tank post right here: GD Gas Tank Swap
I decided to do away with the STi in-tank filter to minimize variables, and keep it as stock V4 STi as possible.
And in the sender went along with all the already figured out lines
Only ended up breaking the top 4 studs for the rollover valve cover. Ended up being able to get two opposing nuts on it, so it should be good.
Put the tank back in without hassle. Then I moved the remaining fuel over from the old tank into the new tank...
Once I started it up everything worked great with the exception of the fuel gauge. It was stuck on 0, but I was bucking and growling like crazy like I was out of gas, so I figured I was super low (I was) and headed to the gas station. Filled it up and I still didn't have a fuel gauge so I grabbed the old senders and did some testing:
As it turns out, the pin (Pin 2 on the sender connector) that the STi sender uses as a ground for the fuel gauge literally just terminates at the next connector in the RS harness and doesn't go anywhere. The RS uses pin 5 on the sender connector as a ground, so I just wired it up so that pin 2 went to pin 5 and the ground was made.
My logic in diagram form:
Pin 2 further down in the harness:
Pin 5 further down in the harness:
Pulled great at WOT through 3rd and I can't wait to really get into some turns to put the surge box to good use. SUCK ON IT STi GUYS!