N54 HPFP Conversion N55 Vacuum pump with B58 HPFP

Lowboost35

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Hello thinking if any one have done it. N54 swaped vacuum pump from N55 part.no:

11667611115 that will accept B58, N63 style HPFP.​

Already purchased vacuum pump and thinking what pump to purchase for this experiment. If any one have any data or advise wellcome to share.
Maybe someone already try this and this solution doesn't work.
 
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wheela

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Assuming the vacuum pump swaps over, have you considered Dorch stage 1 or stage 2 hpfp? Both flow more than the b58 hpfp.

Are you swapping this onto an n54, or an early n55 that came with the n54 vac pump/hpfp?
 

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wheela

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Also, if you're going to swap to n55 vacuum pump, you could consider that Dorch now sells the hpfp lift kit, which is an updated vacuum pump that extracts even more flow from the hpfp. They have two models, 38% more and 49% more flow:
 

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Lowboost35

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It is important to find out if this modification will work before buying a upgraded pump.
Stock N54 Rotary HPFP have solenoidcontrol by DME PWM signal 2pins. B58 pump also have 2 pins.
N55 vac pump / fuel pump housing also have cam possition sensor i question i can just leave it not connected.

Its will be easy solution to fix old n54 hpfp nightmares. Instead helix or other aftermarket solutions. But if this will be that simple i ques its will be also bolton aftermarket product on market.
 

wheela

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It is important to find out if this modification will work before buying a upgraded pump.
Stock N54 Rotary HPFP have solenoidcontrol by DME PWM signal 2pins. B58 pump also have 2 pins.
N55 vac pump / fuel pump housing also have cam possition sensor i question i can just leave it not connected.
Good question. I know I've seen threads of people attempting the swap, but I don't recall if they followed up regarding if they were successful. Since the n55/b58 style pumps are piston based, it makes sense that the dme may need to know cam position to properly control the pump. So the n55 vac pump has a cam position sensor, but n54 ones don't?
 

Lowboost35

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Do some research in ista.
<!---->Position sensor, high pressure pump
Position sensor, high pressure pump

The high pressure pump for fuel injection is driven via the extended drive of the mechanical vacuum pump. The vacuum pump is driven via the timing chain from the crankshaft.

The new generation high pressure pumps are monitored by a position sensor. The crankshaft speed is sensed in the process.

The position sensor for the high pressure pump is mounted on the vacuum pump housing.

Functional description

The position sensor senses the position of the high pressure pump with the aid of an increment wheel bolted to the vacuum pump drive. The engine management system uses this to calculate the pump speed. Speed sensing is required to control the fuel quantity from the high pressure pump.

The position sensor for the high pressure pump essentially functions like a camshaft sensor.


The output signal from the sensor, which is transmitted to the DME, is a square wave signal. Here an electrical high level corresponds to a gap and an electrical low level to a tooth.
 

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wheela

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I remembered this thread, have you seen it before?


There's a lot going on in this thread and details about hpfp setup are sparse, but it sounds like Bahn is using an n54 DME to run both an n54 style and an n55 style hpfp with his setup. If that's true some of the guys in this thread should know what's involved in getting an n55 pump to run with an n54 DME. Maybe tag some of those guys?
 
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carabuser

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I wouldn't want to put the time into something like that unless I needed it myself. Probably a good few weeks of work to develop something like that assuming it needs program sector changes.

If there are people that want to dig deeper and play around themselves I can support with the DME side of things. I have a small windows app that I use to flash my own vehicles with custom DME code (BOOT, PRG and CAL flashing) and I'd happily put it up for free on these forums if there's appetite for custom DME work in the community.