DIY: Stage 2 LPFP

[RJ019]

I wanted to run an ethanol blend map so I decided to do a Stage 2 LPFP upgrade. While researching I couldn't find a DIY for a Stage 2 LPFP build?! So I though I might as well take some picture while I did mine and document it. Hopefully this will be helpful for someone looking to do theirs in the future.

Total cost was only around $230 AU. I'm currently running MHD E40 OTS map and LPFP is holding up strong... Happy Days

Parts used:
- Walbro pump (F90000274)
- Aeroflow Push-in Fuel Fitting 5/16" (AF810-05BLK)
- Aeroflow T-piece 5/16" (AF64-4204BLK)
- Gates Submersible 5/16" 300mm SAEJ30R10
- Stainless Steel Hose Clamps x3
- Stainless Steel Screws x3
- Cable ties

Note: if you are thinking of running E85 I would not use this Gates fuel hose as it is not rated for it, you would need to use something specific for that need. Something like Aeroflow 400 series would be fine, however you can not use normal unleaded fuel with this hose in tank.

Remove rear seat.


Remove bolts.


Pull up cover, see how dirty it is under there.


Disconnect plugs and vent hose and give it a good vacuum and clean.


Remove metal ring. I used a long socket piece and a hammer and tapped it anticlockwise.


Use a flat head screw driver to carefully pry out the fuel pump.


Remove vent hose and pull top hat up.


Disconnect all hoses and plugs.


Pull fuel pump bucket out.


Use a hair dryer/heat gun and flat head screw driver and knife to carefully remove the top black plastic bracket peice.


Do the same for the fuel pump bracket.


Should look like this all out.


Empty bucket.






Old v New.


T-Piece and Quick Connect.


I used a dremel to cut and sand the T-piece on all 3 sides to make it shorter.


I then decided to shorten the fuel pump nipple a bit, to reduce the chance of clearance issues with the top hat.


Rolled up a tissue and put it in the nipple so nothing fell inside the pump. Used a sharp razor to cut the top of the nipple off.


Use some tweezers to pull the tissue out.




Cut the fuel hose and start connecting.


Should look like this when done.


Drill pilot holes into the fuel pump bracket and screw in the screws


You will need to cut the little loops on the pump bracket then it should fit the new pump.


Connect long piece of fuel hose to the venturi. I tried to use a stainless steel hose clamp on this but the nipple on the venturi is very small and it did not hold properly. I ended up using a cable tie to securely hold it on. I made sure it wouldn't fall off, using another cable tie around the hose and a number of others to hold it to the actual venturi.


Doesn't look pretty but that hose is not coming off!


Drill some small holes for cable ties to hold the venturi in place, I also did one for the hose so it wouldn't budge either.




Test fit the fuel pump and mark the fuel pump bracket location on the bucket so you can drill the 3 holes for the screws.




Screw the pump bracket in place and use some cable ties to hold the venturi hose off the side of the bucket.


Connect up wires for the fuel pump to the factory wiring. Put the top plastic bracket on and use cable ties to hold it in place. Note you will need to trim it a bit to be able to fit the new pump. There are holes on the top that you can thread cable ties in and attach them to the fuel pump bracket.




Put the fuel level unit and top hat back on connect both plugs. All done, now just put the fuel pump back doing removal steps in reverse.

[TheFox]

I was actually considering doing this instead of paying the BMW tax. Do you have a parts list of what you bought for the fittings and wiring harness?

Any issues with the install or things you would do different?

[Aus335iguy]

Great write up mate... Can you confirm that theres a return line from somewhere that empties into the bucket ? I think i read in the other thread that you dont really NEED the Venturi connection because the bucket gets filled by the return most of the time and the Venturi is just so that you get all of the fuel from the bottom of the tank ... I can see a second hose in the pics it its not clear where it goes. Whilst this is a bit involved i reckon its worth the savings in dough. Well done!

[Aus335iguy]

For those googling there are two variants of the walbro e85 pumps that can do 450 LPH

I found this on another forum (its on the internet so it must be true eh ?)
?I spoke with Walbro and they stated the difference between the pumps is that the 274 is a high pressure version of the 267. Per Walbro the 267 max pressure is 87psi and the 274 max is 112psi.?

From yet another forum
274 pressure release valve starts opening at 110 psi
267 pressure release valve starts opening at 90 psi

So the 274 may be a better one to buy though they are both rated at max 450LPH

[07tundra]

This is a nice write up no doubt but so many connections and also is that gates hose? There is no need for refilling the bucket that is wasted flow that should be going to the motor. I have a customer running my setup ST 26psi+ and running beautifully with e85. Concentration not sure yet as he is still tuning and he will post once done. But good job with this DIY as most people are terrified to do stuff like this!