DIY : PTFE line- tank to HPFP + inline fuel filter upgrade

[CantSitStill]

Interesting. Are you talking about just pump gas? I use meth that outputs a signal to the dme to up the timing to 10 degrees and 25-26 psi. Been running that for about a year but occasional use.

Meth off 21 psi, meth on and 25psi

100% meth 1400cc/min. Port injectio

datazap.me | Stuie1982 | Wedge v10

datazap.me

 

[martymil]

boost is boost doesn't matter about fuel type, occasional use will help make it last longer but it's only a ticking bomb of when.

When running perfectly it helps but when things go wrong like missfires and cylinder shut downs can really hurt and engine
quickly at anything over 20 psi.

 

[CantSitStill]

Based on the dyno I don't think I'm pushing it but probably near the limit. 500whp should be fine on a stock block, 600whp pushing it, 700whp won't run for long. 600whp is where I'm at with the meth. The meth, especially port meth should help over pump for sure. I would rather run boost than loads of timing or a mix of both. End of day its all about cylinder pressures

 

[E90TT]

Good info here. Thank you!

 

[proboner]

Is there theoretically any need to re-tune after performing mods of this nature?

 

[NoGuru]

Is there theoretically any need to re-tune after performing mods of this nature?

No, you should not need a re-tune.

 

[kulixo]

I just finished some fuel upgrades and wow what a difference.
Can really recommend this for anyone else struggling like I was.
Was running something similar as suggested (AN6 with inline filter from tank, drilled fuel rail, removed HPFP filter and bypassed in-tank filter) but was still struggling to maintain good pressure, even when running a Walbro 535 + one 450.

Decided to build a completely new system:
- Catch tank with Walbro 535 + 450.
- Stock fuel pump to feed catch tank
- AN8 lines from catch tank, splitted into 2x AN6 for HPFP and PI.
- Inline filter
- External FPR

Finally the pressure doesn't ever fall below 70psi, and this is with a single 535. The 450 is not even needed anymore.

 

[proboner]

I just finished some fuel upgrades and wow what a difference.
Can really recommend this for anyone else struggling like I was.
Was running something similar as suggested (AN6 with inline filter from tank, drilled fuel rail, removed HPFP filter and bypassed in-tank filter) but was still struggling to maintain good pressure, even when running a Walbro 535 + one 450.

Decided to build a completely new system:
- Catch tank with Walbro 535 + 450.
- Stock fuel pump to feed catch tank
- AN8 lines from catch tank, splitted into 2x AN6 for HPFP and PI.
- Inline filter
- External FPR

Finally the pressure doesn't ever fall below 70psi, and this is with a single 535. The 450 is not even needed anymore.

It just feels like going full DI delete is cheaper, simpler, and easier at this point

 

[nedrobmas]

Found this during rebuilding my hpfp. Has anyone confirmed the stock hpfp filter micron size? I damaged taking out minds but plans for upgrades. I read injector dynamics fuel filter with the info n testing, but also see fuel lab filter as a suggestion, why one over the other?

I though of a filler neck filter when pumping gas that can be inserted as first line of defense. Im also interested in finding out filter size in the regulator.

 

[fmorelli]

The HPFP inline filter is a bad idea, like all filters (oil, fuel, otherwise) that seems to be inline (VANOS et al). That said, you can also look at Radian - they have a less expensive filter than Fuelabs. You can run that inline, like under the car, then run a non check valve LPFP like the 535 (0295 Walbro pump) that will give you more flow and keep draw within what an EKPM3 can handle.

 

[oVeRdOsE]

did the fuel rail mod, 11/64'', since I had issue with fuel.

(6262 st, 450lph, meth 600cc 50/50)


did a log this morning.


hpfp start with 1950psi and end at 7000rpm at 1500psi. wayyyyyy better !
Before : 750psi @7000rpm


Same for the lpfp, start 72psi to 64psi.
Before : 71psi to 54psi.



I'm 80% convinced the issue was the LPFP, hose clamps did puncture the rubber hose, BUT I didn't see any split or holes.... Now using real fuel clamps, the smooth one. can't tell which work did the difference, I did recheck my LPFP hose, then fuel rail mod without logs.

The log is clean, but the car felt slower... maybe im tire for a monday morning

Major difference on logs :

previous log HPFP/lpfp crashing

new log with fuel rail mod