Di filter & LPFP restriction Line

[martymil]

Di filter & LPFP restriction Line

I don't know if this has been covered but here goes.

So my di pump was always on the limits and dipping below 10 on the jb4 scale and as low as 7

While I was having a good look at an old di pump on the work bench I had a good look at the inlet and found that it has a very restrictive filter.

But before removing the filter and not running one I went out and brought a 10 micron 175gph filter from earls and installed it on the car, which will make it an overkill in term of filtration but no such thing as over filtration unless it causes a restriction.

At the same time I had a good look at the stainless lpfp line and it has 2 very restrictive bends which I was not fond of and after measuring them I found them quite smaller than the inlet port on the di pump.

The first part of the lpfp line that joins the pump is great with no restriction but the line steps down a size after the LPFP sensor and the bends in the line are quite restrictive

I went off to earls and we came up with the new line and the results are pretty impressive

My di pump never dips below 10 and the lpfp line pressure is nice and solid

This worked for me, its up to you if you want to try it and at your own risk and responsibility
and any part of the fuel system should be worked on by a competent mechanic.


This is with di filter in place

http://datazap.me/u/martymil/log-149...ta=1-4-5-10-17

This is with filter removed and 10 micron filter installed under the car but with the stainless line still in place, removing the di filter has the greatest effect on the pressures

http://datazap.me/u/martymil/log-149...ta=1-4-5-10-17

This is with the stainless LPFP replaced with the new one, I haven't been able to get to the track yet for a proper log but you can see there is a slight improvement, any improvement is good

http://datazap.me/u/martymil/log-149...=1-4-5-9-10-17

[Traf]

I wish i had a "earsl" near me lol, nice i'll try that. There's no little gain !

[TwistedTuning]

One of the many finds i've seen on these car. including the HPFP to Fuel rail line which i've made an upgrade for. Good job on the inline filter. the filter on my DI pump has been removed for months honestly with no issues. I didnt bother with an inline filter due to just replacing the pump socks in the tank.

[ninjacoupe]

One of the many finds i've seen on these car. including the HPFP to Fuel rail line which i've made an upgrade for. Good job on the inline filter. the filter on my DI pump has been removed for months honestly with no issues. I didnt bother with an inline filter due to just replacing the pump socks in the tank.

Are you planning on selling this upgrade to the public or is this a strictly DIY?

[TwistedTuning]

Are you planning on selling this upgrade to the public or is this a strictly DIY?

i can.

[Traf]

i can.

Picture ?

[TwistedTuning]

Picture ?

Here...just snapped it real quick going to the grocery store.

[Traf]

It's braided ptfe ?

[martymil]

Im making one atm but out of stainless hard line, dont trust rubber to hold di pressure

Why the hell did bmw restrict our pumps like this, bloody stupid.

[TwistedTuning]

It's braided ptfe ?

yes, special grade PTFE for Ethanol rated at 3000psi working pressure and even higher burst pressure. Have had it installed for several months thus far. i have a lot of stuff i've been working on but don't post much about them until i release.

[martymil]

So got the car on the dyno with the new lpfp line and the fuel rail drilled out to the same size as the bigger internal hole

It surly made a big difference, especially in the timing.

and since the timing was so good on 98 I put an extra psi into the top end

http://www.datazap.me/u/martymil/log-1496638785?log=0&data=1-3-4-8-10-11-14-17-25-26-27-28-29

[martymil]

yes, special grade PTFE for Ethanol rated at 3000psi working pressure and even higher burst pressure. Have had it installed for several months thus far. i have a lot of stuff i've been working on but don't post much about them until i release.

I'd be interested in this too and when can you make me one about 1m long, couldn't be stuffed waiting for the fabricator

[Brule]

What's the white thing? And where is it

[Traf]

What's the white thing? And where is it

Looks like the DI rail

[martymil]

Yes its the di rail inlet

[Traf]

It's crazy how small the hole is.... What could be the reason behind that ?

[CobraMarty]

So got the car on the dyno with the new lpfp line and the fuel rail drilled out to the same size as the bigger internal hole

It surly made a big difference, especially in the timing.

and since the timing was so good on 98 I put an extra psi into the top end

How does that dyno curve compare to BEFORE mods?

Last dyno I found was347hp.

[Tony@VargasTurboTech]

Welcome to 2012. Believe I made this exact post back then, including the filters, and rail. Funny how things get ignored, then "rediscovered"

[Tony@VargasTurboTech]

One of the many finds i've seen on these car. including the HPFP to Fuel rail line which i've made an upgrade for. Good job on the inline filter. the filter on my DI pump has been removed for months honestly with no issues. I didnt bother with an inline filter due to just replacing the pump socks in the tank.

Um, literally face palming. If anyone wants an upgraded line. That is 6000 psi burst, AND The proper fittings for the pump, and rail. We have them in stock. This person is trying to sell you a 3000 psi line, for a system that we routinely run at almost 4000 psi. Sounds like a good plan. We figured all this stuff out years ago, no one is going to figure out things we have not already discovered on this system. If anyone has any questions, we can easily answer them. We are making 800WHP on DI only, no one else is. Many people said it wasn't possible. As for LPFP line going to the HPFP, complete, and utter waste of time. There is no restriction in the line, they use a small hole to the sensor, that is it.

[martymil]

Sorry Tony but I went looking for previous posts on this and I could not find nothing on di filters or anyone else doing this. The logs are there and there is a small improvement in the upgraded line

No one is telling you to change it, just posting the findings and has anyone else done this ?

I rather run the bigger line and the better inline filter than this factory rubbish and that is just the first bend in the factory stainless line for a few measly dollars

[martymil]

The only part of the original line that gets reused is the connection to the pump and the rest is discarded

The one on the right is the first bend in the line that I cut in half to show how restrictive it is.

You can build this line for around 20 dollars USD, no brainer which one I'd choose

Never seen posts on Di filter removal but Id rather run a inline filter and protect my pump especially when the filter runs a 10 micro washable stainless filter that flows 175gph than that tiny highly restrictive filter

[martymil]

How does that dyno curve compare to BEFORE mods?

Last dyno I found was347hp.

The previous was around 347 to 350 rwk but the hpfp was right on the limit check out the first log in the first post

Now Im running 359rwk on 98 with higher hpfp pressures and higher timing and still have a bit of room for more boost if I want

before and after the mods

170605_1328.csv170501_1707.csv

[Tony@VargasTurboTech]

When people post "discoveries" that were posted 4 years previous on the same forum...

[martymil]

So prove it, as if im going to look through 5 year old posts when a simple search doesnt bring anything up

[TwistedTuning]

Um, literally face palming. If anyone wants an upgraded line. That is 6000 psi burst, AND The proper fittings for the pump, and rail. We have them in stock. This person is trying to sell you a 3000 psi line, for a system that we routinely run at almost 4000 psi. Sounds like a good plan. We figured all this stuff out years ago, no one is going to figure out things we have not already discovered on this system. If anyone has any questions, we can easily answer them. We are making 800WHP on DI only, no one else is. Many people said it wasn't possible. As for LPFP line going to the HPFP, complete, and utter waste of time. There is no restriction in the line, they use a small hole to the sensor, that is it.

you are the only one running 4000psi. i made a line "With Proper Fittings" for the pressure that 99% of people would run. Oh, its not like i can't use a higher rated hose if someones build needed it, lmao. My car doesn't see more than 3000psi (working pressure, not burst pressure which is FAR higher) as there is no reason to. And i was never selling anything. hence why no one knew about it. someone asked, and i said sure.

And i'm pretty sure I am not one of those people who said it wasn't possible. its quite simple. You need more fuel, increase fuel output from the pump, add a pump, or add secondary injection.....lol. Theres no rocket science to it. You chose to overdrive pumps. or use two.

So thats the only way to skin a cat apparently. lol. $#@! off. FYI- i've been around dealing with DI before it was a thing. so this isn't my first go around. And i don't go searching for old ass posts about something thats obviously non-existent.