If you're concerned about overpressure the easiest way would be to add an aftermarket FPR / return line and deleting the stock FPR on the fuel sender.
I'm not sure on your exact question or setup. Fuel and power goals?
Teaser: DIY stage 4 fuel system
- Thread starter veer90
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- diy fpr lpfp stage 4 walbro 450 walbro 525
If you're concerned about overpressure the easiest way would be to add an aftermarket FPR / return line and deleting the stock FPR on the fuel sender.
I'm not sure on your exact question or setup. Fuel and power goals?
Good stuff.
That 90 degree fitting fits under the black cover? The barb elbow I used barely fit and I had to cut that down
Oh yeah easily, it actually sits below the ledge so the cap doesnt even touch it
That second pic is a side profile with the 90 attached, i didnt even thread it all the way down, so it actually should it sit a little lower
That second pic is a side profile with the 90 attached, i didnt even thread it all the way down, so it actually should it sit a little lower
Nice work. It's funny how topics are a matter of perspective. On the E89 there is one fuel tank access hole. It''s under the car. Drop the rear exhaust, heat shield, unravel the fuel lines to the fuel housing, empty the tank (good luck - two humps, never clear which one is being drained - murphy's law, not the one you want drained, and then even after it is drained, it is never completely empty so it is just going to piss all over you). Then ... in the hole is the filter, and then further inside (go ahead and reach in) is the LPFP. I'd kill to have 5 minute access to a fuel filter and LPFP under a seat, a few plate bolts, and a quick twist of a screw top lol! I'm not sure if that filter is actually shitty? It protects the LPFP I suppose and reduces filtration for the later, finer HPFP filter. Is the Russell, likely installed under the car, easier to service than the in tank filter?
Nice work! I'm just generally envious
Filippo
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Nice work. It's funny how topics are a matter of perspective. On the E89 there is one fuel tank access hole. It''s under the car. Drop the rear exhaust, heat shield, unravel the fuel lines to the fuel housing, empty the tank (good luck - two humps, never clear which one is being drained - murphy's law, not the one you want drained, and then even after it is drained, it is never completely empty so it is just going to piss all over you). Then ... in the hole is the filter, and then further inside (go ahead and reach in) is the LPFP. I'd kill to have 5 minute access to a fuel filter and LPFP under a seat, a few plate bolts, and a quick twist of a screw top lol! I'm not sure if that filter is actually shitty? It protects the LPFP I suppose and reduces filtration for the later, finer HPFP filter. Is the Russell, likely installed under the car, easier to service than the in tank filter?
Nice work! I'm just generally envious
Filippo
The intank filter is one of the biggest restrictions in the fuel system and cant be serviced at all, its one of those "lifetime" filters, only thing you can do is change out the entire assy which costs 170-200 bucks for a replacement, the russel is under my car and a filter replacement costs only 5, and once under the car its just 2 an fittings i unscrew then the filter is in my hand. So by doing what i did i bypassed a big restriction and made servicing the filter cheaper and quicker.
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Sorry for the late reply but im re reading this and i think you meant the fuel pump strainer (filter that attaches to the bottom of the pump itself) that is still present and attached the pump, what im referring to is attached to the bottom of the hat on the driver side. Thats the one i bypassed that is a restrictionNice work. It's funny how topics are a matter of perspective. On the E89 there is one fuel tank access hole. It''s under the car. Drop the rear exhaust, heat shield, unravel the fuel lines to the fuel housing, empty the tank (good luck - two humps, never clear which one is being drained - murphy's law, not the one you want drained, and then even after it is drained, it is never completely empty so it is just going to piss all over you). Then ... in the hole is the filter, and then further inside (go ahead and reach in) is the LPFP. I'd kill to have 5 minute access to a fuel filter and LPFP under a seat, a few plate bolts, and a quick twist of a screw top lol! I'm not sure if that filter is actually shitty? It protects the LPFP I suppose and reduces filtration for the later, finer HPFP filter. Is the Russell, likely installed under the car, easier to service than the in tank filter?
Nice work! I'm just generally envious
Filippo
Updates are slow since it's winter here and I low key wanna die every time I go work on my car. But my dumb ass managed to fry the EKP this weekend.
I tried a new design for the harness and the EKP did not like it. Despite the fact I had a diode wired in line, power from the battery must have back fed somehow and fried it. However the rest of the EKP seems to be working perfectly fine - the car "sees" the fuel pump, it just can't power it - no yellow "service needed" car on lift icon in the cluster, only a DME fault code (that can be disabled): CDA6 - Message (status, electric fuel pump, 0x335) faulty, receiver DME, transmitter EKP.
This actually worked out, as I had originally planned hard wiring both pumps anyways. Rewired the relay to ignition switched using the cigarette lighter fuse in the glove box, added a kill switch for the pumps in the armrest storage space so I don't kill the battery while flashing tunes, and all is well.
Here's the circuit:
As installed:
I tried a new design for the harness and the EKP did not like it. Despite the fact I had a diode wired in line, power from the battery must have back fed somehow and fried it. However the rest of the EKP seems to be working perfectly fine - the car "sees" the fuel pump, it just can't power it - no yellow "service needed" car on lift icon in the cluster, only a DME fault code (that can be disabled): CDA6 - Message (status, electric fuel pump, 0x335) faulty, receiver DME, transmitter EKP.
This actually worked out, as I had originally planned hard wiring both pumps anyways. Rewired the relay to ignition switched using the cigarette lighter fuse in the glove box, added a kill switch for the pumps in the armrest storage space so I don't kill the battery while flashing tunes, and all is well.
Here's the circuit:
As installed:
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@veer90 Thanks for the thread. My setup is fuelit stage 4 with 6 micron external filter, all fuel lines upgraded, external FPR, Pi etc.
I decided to keep the stock connection for the filter bypass instead of using bulkhead fittings. Thanks again.
I decided to keep the stock connection for the filter bypass instead of using bulkhead fittings. Thanks again.
Mind sharing some pics of how you bypassed the stock filter while retaining the factory feed connection! Id prefer to do it that way down the road!
A dremmel & patience. I cut up a few hats before to understand the restrictions...so the bypass was all part of the fun. The stump to connect the corrugated fuel hose to is not very long but enough to fit a clamp solid around it or one can dremmel away another inch or so for more clearance. I heat up the fuel line to push it over and while it was still warm clamp it down. The connection
felt pretty tight and solid.
That's great, definitely save a lot of headaches for anyone doing this if they can simply remove the paper filter and there's a barb inside.
Like I said, the hardest part was making the whole thing fit. This way is much cleaner.
Like I said, the hardest part was making the whole thing fit. This way is much cleaner.
what kind of incompatibility are we talking? if it's just surface corrosion I should be fine lol
Puts on fake scientist coat
Probably fine, you're like "N54 guy #194" who's done that. Just for reference to others who want to tackle the project.
Next time you open the tank up I'd swap it out.
McMaster-Carr has what is needed
McMaster-Carr
McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
Puts on fake scientist coat
Probably fine, you're like "N54 guy #194" who's done that. Just for reference to others who want to tackle the project.
Next time you open the tank up I'd swap it out.
McMaster-Carr has what is needed
McMaster-Carr
McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.www.mcmaster.com
If you have evidence of brass fittings corroding through or causing fuel system damage I would love to see it. Serious, not trying to be a dick.
I chose brass based on a different chemical compatibility sheet: http://catalog.gpi.net/Asset/Chemical-Compatibility-Ver-6.pdf
Lists brass as "recommended" for ethyl alchol and most hydrocarbons.
