Hi everyone. I'm sharing with you what I modified in the low pressure fuel system to remove the original restrictions.
Thanks to vasiliy salogub who inspired me by this link https://www.facebook.com/groups/N54tech/permalink/2111380402550376?locale=fr_FR
When I was at full load, I had a problem. My pressure was dropping to 62 psi despite my 2 pumps. So I decided to modify the whole line that goes from my 2 pumps (main wabro 535, secondary 525) to the rigid line of the HPFP. The goal is to supply the original line (venturi in the second part of the tank) with the walbro 535 and bypass the venturi for the second line with a walbro 525. The second pump will have its own line and will not be connected to the black market parts Y line as we are used to seeing.
Everything was done with AN6
What I used:
AN6 90 Male Female x3
AN6 Female to 5/16 Barb x2 for Second Pump Line
AN6 female to 1/4 barb x1 for regulator line
AN6 male to 1/4 barb X1 for main pump line (hole enlarged and drilled to 5mm)
Transparent Corrugated Nylon Hose 1000mm ID 8mm Od 10mm For Second Pump Line
Quick coupling AN6 5/16 x1
Passe cloison AN6 x1
T AN6 Male Female x1
Y AN6
AN6 90 female female x2 1 for principal line and 1 to connect T to Y
AN6 90 female to AN6 PTFE hose x1
Tool to insert nylon hose on barb
It cost me 200$ line, fuel filter and tool included (50$ for the tool)
1) Disassembling the pressure regulator. By pulling on it and turning it, you can get it out completely.
2) Original filter cutout. I used a dremel connected to a drill.
3) Assembling all AN6. The white line goes to the second pump and the brown original line to the the main pump. The first photo was the first edit. The others are the final assembly.
The black hood closes. It press a little on the rubber.
4) PTFE AN6 line mount with in-line filter. For this part I used this post:
https://www.spoolstreet.com/threads/ptfe-line-tank-to-hpfp-inline-fuel-filter-upgrade.3041/
Result:
Before
https://www.spoolstreet.com/graphs/before.34457/?series=0,3,16&zoom=-2,164
After
https://www.spoolstreet.com/graphs/after.34458/?series=0,3,16&zoom=-2,155
Originally I modified this because I thought it would take away the timing I have on cylinder 5. It hasn't changed anything at this level, but the lpfp is much better. I go from 62 psi to an average of 77psi. The minimum observed on my logs under the same conditions is 72 psi. I hope it will help other people. If anyone has an idea how to fix the timing problem on cylinder 5 and 2 I'm all for it (compression ok, injector ok, spark plug ok, coil ok). I think it's tune related. If anyone would like to look at my tune i would really appreciate it.
my mods
E93 DCT N54
speedtech bottom mount GTW3884R 6766
port injection 1300cc
Full E85
JB4
self tuned
...
Sorry for my bad English, I'm French.
Thanks to vasiliy salogub who inspired me by this link https://www.facebook.com/groups/N54tech/permalink/2111380402550376?locale=fr_FR
When I was at full load, I had a problem. My pressure was dropping to 62 psi despite my 2 pumps. So I decided to modify the whole line that goes from my 2 pumps (main wabro 535, secondary 525) to the rigid line of the HPFP. The goal is to supply the original line (venturi in the second part of the tank) with the walbro 535 and bypass the venturi for the second line with a walbro 525. The second pump will have its own line and will not be connected to the black market parts Y line as we are used to seeing.
Everything was done with AN6
What I used:
AN6 90 Male Female x3
AN6 Female to 5/16 Barb x2 for Second Pump Line
AN6 female to 1/4 barb x1 for regulator line
AN6 male to 1/4 barb X1 for main pump line (hole enlarged and drilled to 5mm)
Transparent Corrugated Nylon Hose 1000mm ID 8mm Od 10mm For Second Pump Line
Quick coupling AN6 5/16 x1
Passe cloison AN6 x1
T AN6 Male Female x1
Y AN6
AN6 90 female female x2 1 for principal line and 1 to connect T to Y
AN6 90 female to AN6 PTFE hose x1
Tool to insert nylon hose on barb
It cost me 200$ line, fuel filter and tool included (50$ for the tool)
1) Disassembling the pressure regulator. By pulling on it and turning it, you can get it out completely.
2) Original filter cutout. I used a dremel connected to a drill.
3) Assembling all AN6. The white line goes to the second pump and the brown original line to the the main pump. The first photo was the first edit. The others are the final assembly.
The black hood closes. It press a little on the rubber.
4) PTFE AN6 line mount with in-line filter. For this part I used this post:
https://www.spoolstreet.com/threads/ptfe-line-tank-to-hpfp-inline-fuel-filter-upgrade.3041/
Result:
Before
https://www.spoolstreet.com/graphs/before.34457/?series=0,3,16&zoom=-2,164
After
https://www.spoolstreet.com/graphs/after.34458/?series=0,3,16&zoom=-2,155
Originally I modified this because I thought it would take away the timing I have on cylinder 5. It hasn't changed anything at this level, but the lpfp is much better. I go from 62 psi to an average of 77psi. The minimum observed on my logs under the same conditions is 72 psi. I hope it will help other people. If anyone has an idea how to fix the timing problem on cylinder 5 and 2 I'm all for it (compression ok, injector ok, spark plug ok, coil ok). I think it's tune related. If anyone would like to look at my tune i would really appreciate it.
my mods
E93 DCT N54
speedtech bottom mount GTW3884R 6766
port injection 1300cc
Full E85
JB4
self tuned
...
Sorry for my bad English, I'm French.
Attachments
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