Thread: Industrialfish's GTP, added budget rear diffuser.

I finally finished the fuel pump install debacle so time to share it. The pictures are not necessarily in order of operation as I forgot to take some pictures while I was doing the work etc.

This is what the back of an 05+ looks like where the fuel pump access is on all the other cars.

So I went to a junk yard and cut out the sheet metal for the fuel pump access from a 2004. There are 3 ribs and a tab surrounding the pump that the sheet metal is spot welded to, so I drilled/cut out there with the intentions of pop rivet/spot welding it into mine.

While the curvature and weld spots lined up, the 2004 Access Panel DOES NOT line up with the 2005+ gas tank ring mount. So I cut and modified the access panel to line up. Except this is what I found after I pulled the canister.



The 2005+ fuel pump canister is different than the 2004... and doesn't fit through the ****ing access panel anyway. After I finally figured out how to get this pump apart, I go to put my AEM 320LPH E85 fuel pump in aaaaand it doesn't fit right. The 2005+ is a slightly different shaped pump, and even though the AEM pump came with adapters to get it to fit, it had too much play for me. After searching online I found a place that has a 2005+ direct fit Walbro 420lph E85 kit. http://www.highflowfuel.com/i-239064...2005-2009.html

They also had the "non-serviceable" fuel filters for 2005+ so I bought one.



Since I had a replacement on hand, I decided to take apart my factory one to see how the filter looked. Using a tiny screwdriver I slowly pried up the top lip holding the can together. Nothing but a paper filter in there. But wait! Fuel goes in, pressurizes the can and goes through the filter and right back out. Pressure regulator bleeds off any extra pressure back into the pump canister BEFORE the filter. The filter is last in line after all the pump internals. If I can find a suitable filter for under the hood, I can just remove the paper filter in the gas tank and never have to worry about changing it again! With the added benefit of a larger reservoir. So I put it back together minus the filter and crimped the can closed.

Aww yiss. Got a filter from Autozone with 3/8 quick connects on each end.


Now time for the pump rewire. And of course another snag. Both the Casper and ZZP rewire kits have the square 4 connectors and I have the flat 4 connector. I went to the JY and got a square 4 connector from an 6th gen GP pump canister but it didn't fit in my 05 canister, no surprise. I tired in vain to find a replacement pump side connector so I could just make an adapter, but that wasn't happening. So I bit the bullet and traced the pinout of the car harness, pump connector, and both the input and output of the Casper harness and cut the ends off all of them.

Made an adapter out of the Casper connectors and the car harness to make sure I had it wired correct. I didn't, I had the signal wires for the fuel level backwards so it pegged Full and set the CEL.


While soldering the connectors to the the harnesses (no cutting and splicing for this guy!) I noticed that the Casper rewire uses 10Ga wire all the way from the alternator to the 30A relay before the pump, but then uses the same underrated 14Ga for the last 2 feet from the 30A relay to the pump. Although the voltage drop of that little distance is much less than across the length of the car, the whole point of the rewire is to bypass that problem. Fortunately since I ran the rewire inside the car, I had a few few feet extra of the power wire and fixed that problem.



And made my own cover. I used square license plate nuts in the sheet metal to hold it down, and weather strip along the edges. Sealed up nice and finally got to reinstall my carpet after a year of dicking around.



Before all this I was getting 54ish psi at the rail when running that would bleed out to 10psi within minutes of turning the engine off. Now I get 68psi at the rail that drops to 40psi with key off and holds it for at least 10 days.

The universal diffusers on eBay are less than an inch wider than our rear plastic. Not as cool as the SE diffuser, but for $50 it's not terrible.



And yes I have two other pairs of tips to replace the rusting ones.