Technical Was It Ever Considered???....

[Dumaurier7]

Hi all, I am presently getting my N54 car ready for tuning, I've since installed and been running a PFS POD without any issues but looking at the whole set up it seems like the N54 HPFP would be the weak link. This then made me wonder if or why nobody has developed and adapter to be able to use an N55 HPFP which would then allow replacement with an upgraded aftermarket pump?!

 

[aus335iguy]

Multiple different alternatives have been discussed before but don’t recall exactly what the difficulty was in practice

 

[wheela]

I know at least one n55 guy swapped out mating components (vac pump and housing? IDR the details) to switch a block from 1 type to the other, but that was all with an n55 dme. Can the n54 dme control an n55 style hpfp?

 

[JohnDaviz]

N54 Dual HPFP

There has been a bit of forum talk recently of a few different HPFP solutions for the N54 cars so I thought I would give a brief intro into a new possibility - The dual piston style pumps you see here are on my Z4 . So far, development has gone well. The car is driveable but still a ways to go...

www.spoolstreet.com

This was actually one of the most promising projects but it never really finished?!

 

[Dumaurier7]

I know at least one n55 guy swapped out mating components (vac pump and housing? IDR the details) to switch a block from 1 type to the other, but that was all with an n55 dme. Can the n54 dme control an n55 style hpfp?

They both use a two wire solenoid type controller to vary the load on the pump, I will assume it’s the same .

 

[Dumaurier7]

N54 Dual HPFP

There has been a bit of forum talk recently of a few different HPFP solutions for the N54 cars so I thought I would give a brief intro into a new possibility - The dual piston style pumps you see here are on my Z4 . So far, development has gone well. The car is driveable but still a ways to go...

www.spoolstreet.com

This was actually one of the most promising projects but it never really finished?!

Too much complications in my opinion, I don’t think the juice is worth the squeeze. I have the PR/NHP big bore HPFP upgrade and it supplies plenty of fuel! Anything more can be had with their upgraded fuel injectors.

 

[Dumaurier7]

Hi all, I am presently getting my N54 car ready for tuning, I've since installed and been running a PFS POD without any issues but looking at the whole set up it seems like the N54 HPFP would be the weak link. This then made me wonder if or why nobody has developed and adapter to be able to use an N55 HPFP which would then allow replacement with an upgraded aftermarket pump?!

My thinking here is to somehow find a way to totally eliminate the problematic OEM pump, I am fortunate thus far to not have had any HPFP related issues but I know that it is inevitable .

 

[SLOWESTN54]

Is two fuel pumps worth the effort. The S58 in the M3 comes with two factory TU pumps, that fuel system still caps out at 850whp.

 

[wheela]

Is two fuel pumps worth the effort. The S58 in the M3 comes with two factory TU pumps, that fuel system still caps out at 850whp.

Imagine throwing a couple Dorches in their place..

 

[SLOWESTN54]

Imagine throwing a couple Dorches in their place..

Sorry it was with two spool FX350's witch are the equivalent to two dorch stage 2's. Alongside their upgraded Di injectors, On a E50 mix. on full E85 it could only support 780wheel.

 

[wheela]

Different motor, but the Dorch lift kit for s55 uses the two factory hpfp's, and they say it's limited by injectors at 800whp on e85, but could support more if higher flowing injectors existed.

 

[Dumaurier7]

If the original design utilizes two HPFP’s I would still be an advocate of developing the OEM DI system to the highest level , as a matter of fact, once the incumbent system proves RELIABLE it should not be altered but improved . In the case of the N54/55 engines as we know, they were not fitted with twin pumps which is why I have stated that it’s not worth the effort to try and adapt the S55 dual pumps. Due to past experiences, limited resources and time I will almost always strongly agree with improving and perfecting on the existing OEM design. Going in a totally different direction will require engineering , manufacturing and programming know how together with a host of other resources which are not usually available to the average DIY’er. In the case of my N54 and N55 I will be developing the DI systems to their maximum limits whilst incorporating Pl as I also believe PI is very flexible and has its place.

 

[wheela]

If the original design utilizes two HPFP’s I would still be an advocate of developing the OEM DI system to the highest level , as a matter of fact, once the incumbent system proves RELIABLE it should not be altered but improved . In the case of the N54/55 engines as we know, they were not fitted with twin pumps which is why I have stated that it’s not worth the effort to try and adapt the S55 dual pumps. Due to past experiences, limited resources and time I will almost always strongly agree with improving and perfecting on the existing OEM design. Going in a totally different direction will require engineering , manufacturing and programming know how together with a host of other resources which are not usually available to the average DIY’er. In the case of my N54 and N55 I will be developing the DI systems to their maximum limits whilst incorporating Pl as I also believe PI is very flexible and has its place.

Yeah, I generally agree with that. It's why I wanted to stay with an internally gated vacuum driven wastegate vs. traditional pressure driven wastegate - the DME logic is already set up to control the vacuum based system, and it can still control the wastegate at any boost pressure vs. traditional where you can only control it above spring pressure. Traditional ends up being a different system that the dme wasn't designed to control. But I decided going external gate was worth the tradeoff to get the turbo I wanted.

 

[wheela]

For the s55 folks, the Dorch lift kit with stock pumps is extra nice for this reason. Dorch says because it uses oem pumps, the dme controls it just fine without any additional tuning. That's pretty awesome if true.