[dzenno]

Alright, so, my low pressure fuel pump (LPFP) died on me last night, more info here:

http://www.e90post.com/forums/showthread.php?t=589990

I've had this LPFP put in only a couple months ago while diagnosing and replacing a few parts during my misfire issues. Ever since installing this last LPFP I've also had the Kenne Bell Boost-A-Pump (voltage regulator/amplifier) wired into it. While I doubt it caused the pump to die prematurely its possible. This BAP was wired in and it was always set at the MIN (or lean as they call it on the adjustment knob) setting which is basically a bypass/passthrough mode. Last night while doing some testing of the new race tune I've been playing with (Cobb+jb4) I decided to turn up the BAP setting to MAX (or rich as they call it on the adjustment knob). Now, I've run this max setting before a few times already and there were no issues. After running about 2-3 times with the MAX setting on the BAP, I came off the highway to flash a different map to the car and get back on the highway to retest one last time before hitting the track this morning but that didn't happen. After reflashing I cranked the car and it started but then the engine quickly died. I cranked it again, turns on and dies again right after, doesn't hold idle. I plugged the AP in and used the Monitor feature and saw the LPFP pressure, which is supposed to be 72psi at idle and between cranks (LPFP requested pressure monitor on the AP shows this) the actual fuel pressure was only 15-18psi and wouldn't move. I also wasn't hearing the pump priming at all. At this moment I don't know if it really is the pump or maybe as simple as a fuse but in any case, I've been thinking of trying something else on the car...

The stock in-tank fuel pump is "rated" at 90LPH but we all know it supports more than that as many of us are pushing way more than what the theoretical HP fuel limit is for a 90LPH fuel pump. There are some theories on fuel system limitations on the N54 that hint at ~480-500whp as the stock fuel system limits and I'm not sure what to think of that but given the stock low pressure fuel pump official rating I can't say that I'd disagree much.

So, what can be done is the question...Some of the info has been hinted at on these forums before by Shiv and his part 1 and 2 fuel pump testing and some has already shown partial success by the BMS team by using the Kenne Belle Boost-A-Pump which by many isn't considered a viable long term alternative and in my case, it quite possibly could be the cause behind my 4-5 month premature LPFP failure last night.

One option that I've come across through some Google skills is a Bosch 044 inline fuel pump, specs here:

http://www.boschfuelpumps.com/

The part number of the Bosch 044 pump (ends with 044) are on the above site but I'll past them in here for completeness sake:

==============
Bosch 044 fuel pumps mount inline (out side of your gas tank), most commonly rear center under your car or truck. Each Bosch 044 inline fuel pump provides 300LPH of flow and operate at 72.5 PSI. Bosch 0-580-254-044 fuel pumps are comparable to the Walbro 255LPH high pressure inline fuel pumps which can both support vehicles for up to 600-700 horse power. Can be used in sequence with an intank Walbro or Bosch 040 fuel pump.

Bosch 044 Fuel Pump Specs:
Bosch Part Number: 0580254044
Minimum Current: 12 Volts
Operating Pressure: 72.5 PSI (5 Bar)
Minimum Flow @ Outlet: 80 GPH (300 LPH)
Fuel Pump Location: In-Line
High Temperature Reduction: 8 GPH (30 LPH)
Weight: 1030 Grams (2.27 Pounds)

===========

Now, if you look closely this pump has the clear advantage of 300LPH which is way more than the stock rating of the stock pump. What doesn't sit too well is the following:

==
1) Requires 12volts - the stock fuel pump at idle sits somewhere around 7volts and voltage is regulated by the EKP (fuel pump controller that's above the back seat) anywhere between 7 and 11 volts during WOT which raises pressure sometimes to even 85psi to meet the fuel volume demand coming from the HPFP/motor side. QUESTION: How do we address this? Does it need to be addressed at all and why not just give the pump 12volts all the time?

2) Dimensions - I have a feeling that this pump's dimensions might be slightly larger than the stock pump. If it is bigger then a new bracket will be required for it to make it sit inside the tank properly.

3) Pump is meant as an inline pump, not intank - The Bosch 044 pump is intended to be used as an inline pump. They're VERY noisy pumps but are MANY times more reliable than the Walbro 255lph from everything I've read. I'd like to run just one not two pumps if possible personally, less things to worry about and I'd really like to get rid of the stock fuel pump if at all possible (may not be due to issues stated in 1 above and the stock pump may need to be used as well as the intank and 044 as inline, trying to avoid it). However, it is very encouraging to know that the Bosch 044 CAN be mounted intank as well and that quite a few setups are running this way. Here's an example of such setup on a rotary mazda:

http://mazdarotaryclub.com/forums/sh...ad.php?t=59612

My main concern is the heat the pump gives away, does it run hot, and if/how that'd impact the in-tank fuel temperature.
===

The reason I like the Bosch 044 inside the fuel tank is noise levels will be much reduced and more importantly I'd be running one single pump instead of two so less points of failure. I really don't want to have 3 fuel pumps on the car, that'd be a disaster

Let's get the dialogue going and see what the collective thinks of this or any other setup that you may think would work. What data would you like to gather to support your ideas, etc etc.

One of the key elements required to get the Bosch 044 to work inside the tank is this little 30 micron filter:
http://www.jayracing.com/index.php?m...products_id=62

[dzenno]

It was the 20a fuse that blew making the lpfp unusable flashing the car with the BAP at MAX setting won't be done again! Lol

Still on the quest for a better flowing LPFP though

[CobraMarty]

On that Bosch pump the 'minimum volt requirement of 12v' is concerning.
What about this aeromotive pump:
http://aeromotiveinc.com/products-pa...-center-inlet/

Or can you get 2 stock pumps inside the tank piggy back style.

[OpenFlash]

Originally Posted by CobraMarty

On that Bosch pump the 'minimum volt requirement of 12v' is concerning.
What about this aeromotive pump:
http://aeromotiveinc.com/products-pa...-center-inlet/

Or can you get 2 stock pumps inside the tank piggy back style.

I've tested the Aeromotive in tank replacement pump and it only flows ~10% better than the stocker. And doesn't have a vent for Venturi jet which would then require an external lifter pump which gets messy. Ive also tested their in line pump and it doesn't flow well at high fuel pressure. Also tested the Bosch pump and a few others and they cause the fuel pressure control module to run too hot due to the extra current requirement. So it's a bit more work than Dzenno is suggesting. Which is why I only revealed half the work i did to him. Because I know he would be tempted to spill the beans.

[Jeff@TopGearSolutions]

Originally Posted by shiv@vishnu

I've tested the Aeromotive in tank replacement pump and it only flows ~10% better than the stocker. And doesn't have a vent for Venturi jet. Ive also tested true in line pump and it doesn't flow well at high fuel pressure. Also tested the Bosch pump and a few others and they cause the fuel pressure control module to run too hot due to the extra current requirement. So it's a bit more work than Dzenno is suggesting. Which is why I only revealed half the work i did to him. Because I know he would be tempted to spill the beans.

How about a port fuel injection conversion... problems solved

[OpenFlash]

Originally Posted by Jeff@topgearsolutions

How about a port fuel injection conversion... problems solved

Funny you mention that. My n54 is currently getting a large single turbo installed in it. Which will allow me to test system limits more easily. Right now, with meth+tweaked lpfp system and ASR turbos at 20psi (530whp) I can't be 100% certain I'm bumping up against the fuel limits. But with a big single running 17psi an making 580whp, I should have a better idea

I'll have some pics of the turbo work later this the week. It's a big but fun process. Something that we've been planning for a while. Didnt want to say anything until progress was underway. The point of no return so to speak!

[jpsimon]

Originally Posted by shiv@vishnu

Funny you mention that. My n54 is currently getting a large single turbo installed in it. Which will allow me to test system limits more easily. Right now, with meth+tweaked lpfp system and ASR turbos at 20psi (530whp) I can't be 100% certain I'm bumping up against the fuel limits. But with a big single running 17psi an making 580whp, I should have a better idea

I'll have some pics of the turbo work later this the week. It's a big but fun process. Something that we've been planning for a while.

SAY WHAT

[Brey335i]

Originally Posted by shiv@vishnu

Funny you mention that. My n54 is currently getting a large single turbo installed in it. Which will allow me to test system limits more easily. Right now, with meth+tweaked lpfp system and ASR turbos at 20psi (530whp) I can't be 100% certain I'm bumping up against the fuel limits. But with a big single running 17psi an making 580whp, I should have a better idea

I'll have some pics of the turbo work later this the week. It's a big but fun process. Something that we've been planning for a while. Didnt want to say anything until progress was underway. The point of no return so to speak!

Is this a separate N54 than the shop car? Or did you leave the ASR setup already?

[OpenFlash]

Originally Posted by jpsimon

SAY WHAT

Yep. Work began last week. I'll start another thread later this week with some pictures charting the progress. Hope to have the car running within 2 weeks. The turbo we chose is pretty special

Originally Posted by Brey335i

Is this a separate N54 than the shop car? Or did you leave the ASR setup already?

The ASR set up is getting a nice compressor wheel upgrade and moving to another shop car that we recently acquired. The big single is going in the original shop car since it has all the other chassis upgrades already. And it's getting a cage too.

Sorry for the OT....

[Jeff@TopGearSolutions]

Originally Posted by shiv@vishnu

Funny you mention that. My n54 is currently getting a large single turbo installed in it. Which will allow me to test system limits more easily. Right now, with meth+tweaked lpfp system and ASR turbos at 20psi (530whp) I can't be 100% certain I'm bumping up against the fuel limits. But with a big single running 17psi an making 580whp, I should have a better idea

I'll have some pics of the turbo work later this the week. It's a big but fun process. Something that we've been planning for a while. Didnt want to say anything until progress was underway. The point of no return so to speak!

Well if there actually is a fuel limit ceiling removed (for pump gas) I would actually contemplate on keeping this car and going Single turbo myself. I personally lost interest in this car knowing that I needed to use methanol as a fueling bandaid and with only upgraded stock size turbo's available was even more of a bummer. This will be interesting to see if it works. AS you know there is a lot of vaporware on these forums, especially in regards to single turbo conversions among other things. So dont let us down...

[R1000K3]

I hope some company develops a single turbo replacement kit for about the same cost as e.g. RB's. 600 whp should be fine on this car and a larger turbo may last better.

[SneakyDeeky]

That's crazy! Subscribed.

[R1000K3]

Perhaps a new self-selling product from Vishnu

[Q4P]

Originally Posted by shiv@vishnu

Yep. Work began last week. I'll start another thread later this week with some pictures charting the progress. Hope to have the car running within 2 weeks. The turbo we chose is pretty special



The ASR set up is getting a nice compressor wheel upgrade and moving to another shop car that we recently acquired. The big single is going in the original shop car since it has all the other chassis upgrades already. And it's getting a cage too.

Sorry for the OT....

WHAT??? I hope this is the one... maybe a Garret Unit or PT?

Anyways I can't wait to see this.

[Q4P]

Originally Posted by Jeff@topgearsolutions

Well if there actually is a fuel limit ceiling removed (for pump gas) I would actually contemplate on keeping this car and going Single turbo myself. I personally lost interest in this car knowing that I needed to use methanol as a fueling bandaid and with only upgraded stock size turbo's available was even more of a bummer. This will be interesting to see if it works. AS you know there is a lot of vaporware on these forums, especially in regards to single turbo conversions among other things. So dont let us down... ;)

big time!

Which is why I hope this is for real...

[OpenFlash]

Before anyone gets too excited, this is currently only an engineering exercise of sorts. There are still a lot of unknowns here. The only thing I know with reasonable confidence is that the HPFP either need to be replaced or augmented at 530+whp. Because when running the ASR turbos full out (20+psi), I began to see HPFP rail pressure start to drop. Not enough to cause codes/issues. But enough to raise eyebrows. With the big single, my calculations suggest that that would should be making that power at just 16psi. With another 150whp left on the table assuming an adequate fuel system. So we will learn a lot. If the results are good, we will certainly install some more kits in local cars. And then eventually go full production. But there is a lot to do before then. And in the end, many people not hunting for HUGE hp numbers will be happier with upgraded twins. They will most certainly be more affordable given that they don't require a custom manifold, downpipes, external wastegates and new induction plumbing.

And yes, this is really happening. We decided to go through with it ourselves due to our experience with custom turbo kits and the fact that everyone else was taking so darn long. The engine bay is already torn apart so there really is no going back. I miss my daily driver

Shiv

[Overboost]

Hey Shiv,
Borg warner EFR turbo???

[OpenFlash]

I cannot say at this time

[venom3469]

I can't wait to see the results!

[Overboost]

Originally Posted by shiv@vishnu

I cannot say at this time

Lol Shiv. I won't say a word

[OpenFlash]

Originally Posted by Overboost

Lol Shiv. I won't say a word

I've heard that before

[Overboost]

BTW. Is ASR doing the compressor upgrade or is this another Vishnu performance modification? If the former, why not just make and brand your own twin turbo upgrade?