HPFP difference between early (2011) and late (2013) N55 E90x engine?

jlegelis · 01-15-2018, 10:37 PM

Hi All - The rail pressure on my late (2013) N55 E92 is not holding up well under aggressive MHD-based tunes. I've been told the later N55 HPFP pumps don't flow as well as the earlier pumps (I've already upgraded the LPFP - didn't notice any major change). Can anyone confirm, or offer suggestions on how to improve HPFP flow, or perhaps 'downgrade' to the earlier pump if that's even an option?

Thx,
JohnL
Boston
2013 E92 N55

Toome · 01-16-2018, 09:47 AM

Quote:

Originally Posted by jlegelis

Hi All - The rail pressure on my late (2013) N55 E92 is not holding up well under aggressive MHD-based tunes. I've been told the later N55 HPFP pumps don't flow as well as the earlier pumps (I've already upgraded the LPFP - didn't notice any major change). Can anyone confirm, or offer suggestions on how to improve HPFP flow, or perhaps 'downgrade' to the earlier pump if that's even an option?

Thx,
JohnL
Boston
2013 E92 N55

Only option is to go with port injection until there is a HPFP solution available.

Kevin39 · 01-16-2018, 11:03 AM

Or one of VTTs shotgun kits.

Toome · 01-16-2018, 11:13 AM

Quote:

Originally Posted by Kevin39

Or one of VTTs shotgun kits.

The VTT shotgun kit only works for 2011's.

Turbod · 01-16-2018, 12:36 PM

Yes they changed the HPFP. I believe the change was early 2012. The newer style cannot flow as much as the older style. As mentioned above port injection is the solution. A LPFP upgrade is pointless until you add port injection. If you don't want to go port injection then consider a methanol kit.

A lot of people ask if you can replace your newer style with the older style, you cannot.

bbnks2 · 01-16-2018, 12:48 PM

Quote:

Originally Posted by Turbod

A lot of people ask if you can replace your newer style with the older style, you cannot.

has anyone actually tried this? Real OEM shows that a newer style 2012+ pump can be retrofitted in lieu of older style pumps with the use of an "adapter." If that is true, why wouldn't an older style pump bolt up in place of the newer style pump?

Toome · 01-16-2018, 02:01 PM

Quote:

Originally Posted by bbnks2

Quote:

Originally Posted by Turbod

A lot of people ask if you can replace your newer style with the older style, you cannot.

has anyone actually tried this? Real OEM shows that a newer style 2012+ pump can be retrofitted in lieu of older style pumps with the use of an "adapter." If that is true, why wouldn't an older style pump bolt up in place of the newer style pump?

No the HPFP changed with the DME as well, so it is not a direct swap.

Kevin39 · 01-16-2018, 02:33 PM

Quote:

Originally Posted by Toome

The VTT shotgun kit only works for 2011's.

Ah, good catch. Thanks.

bbnks2 · 01-16-2018, 02:52 PM

Quote:

Originally Posted by Toome

No the HPFP changed with the DME as well, so it is not a direct swap.

Oh that's interesting... DME doesn't control the fuel pump though.The EKP module does. I guess the newer DME sends a different range of PWM voltage or something? Seems like you'd just need to define a few more tables to get it working right... but others know way more than I do...

Toome · 01-16-2018, 02:56 PM

Quote:

Originally Posted by bbnks2

Quote:

Originally Posted by Toome

No the HPFP changed with the DME as well, so it is not a direct swap.

Oh that's interesting... DME doesn't control the fuel pump though.The EKP module does. I guess the newer DME sends a different range of PWM voltage or something? Seems like you'd just need to define a few more tables to get it working right... but others know way more than I do...

Interesting. If the fuel pump voltage could be modified I guess it would work, but no one has tried to do that.

FireBlaze · 01-16-2018, 07:29 PM

Quote:

Originally Posted by Toome

Interesting. If the fuel pump voltage could be modified I guess it would work, but no one has tried to do that.

On my late model N55, I was getting a Fuel Pump warning in the IDrive after I installed the Stg 2 Fuel-It pump due to the increased pump voltage. Joe from TopGearSolutions was able to code the EPK module to increase the voltage threshold so the error went away.

jlegelis · 01-17-2018, 10:40 AM

In my car (2013 E92 N55), I'm seeing rail pressure drops on just the stock turbo with an MHD Stage 2+ tune. Do earlier N55's not experience this? Can those cars go to PS1 with stock fueling?

p.s. Really trying to avoid going to port injection. This car is a DD and trying to avoid a science project

Toome · 01-17-2018, 11:15 AM

Quote:

Originally Posted by jlegelis

In my car (2013 E92 N55), I'm seeing rail pressure drops on just the stock turbo with an MHD Stage 2+ tune. Do earlier N55's not experience this? Can those cars go to PS1 with stock fueling?

p.s. Really trying to avoid going to port injection. This car is a DD and trying to avoid a science project

Can you post a log?

Here is one of mine as a comparison:
https://datazap.me/u/toome/mhd-stage...-19&solo=17-18

FireBlaze · 01-17-2018, 02:06 PM

Here's my fuel pump dip on MHD Stg 2+ log:

https://datazap.me/u/porschet/log-15...og=1&data=4-17

Turbod · 01-17-2018, 03:31 PM

Quote:

Originally Posted by jlegelis

Do earlier N55's not experience this? Can those cars go to PS1 with stock fueling?

Yes the older style can go upgraded turbo with no modifications to the fuel system. I am able to run E30 at 17 - 18 psi and pump at 22 psi before the fuel system starts to crash.

jlegelis · 01-17-2018, 03:33 PM

Here's a 2-3 pull. We've reduced the boost onset a bit in later versions to lessen the dip, but I'm essentially fuel-limited at this point...

https://datazap.me/u/jlegelis/wedge-...-31&solo=11-24

FBO E92 N55 2013, with MHD flash and LPFP. Stock turbo.

juld0zer · 01-18-2018, 02:37 AM

EKPS controls the LPFP.
DME controls the HPFP.

I haven't dealt with this issue personally but a lot of electrical connectors changed with the newer DME. My guess would be that you just need a male connector to suit the old pump and make up an adapter to suit it.

2ndgearmoto · 04-03-2022, 10:33 PM

I have a 2012 335i with older style hpfp. Engine threw a rod so I swapped a 2013 n55. Both fuel pumps connect to the DME but the newer block's fuel pump has 2 electrical connections where my original pump has only 1. Is there a work around so I don't need new wiring harness and dme/ecu?

Tallicia · 02-10-2024, 01:27 PM

Quote:

Originally Posted by 2ndgearmoto

I have a 2012 335i with older style hpfp. Engine threw a rod so I swapped a 2013 n55. Both fuel pumps connect to the DME but the newer block's fuel pump has 2 electrical connections where my original pump has only 1. Is there a work around so I don't need new wiring harness and dme/ecu?

Any update on this?

I have a 2011 N55 E88 old style HPFP and a 2013 N55 E71 newer style HPFP, and I am looking to upgrade both to newer style upgraded HPFPs.

Is there a way to use a newer style "cam" HPFP with early N55 DMEs? a tune and wiring adapter?

fastboatster · 02-11-2024, 03:22 PM

Quote:

Originally Posted by Tallicia

Any update on this?

I have a 2011 N55 E88 old style HPFP and a 2013 N55 E71 newer style HPFP, and I am looking to upgrade both to newer style upgraded HPFPs.

Is there a way to use a newer style "cam" HPFP with early N55 DMEs? a tune and wiring adapter?

no, the biggest problem is that the newer style pump needs a different vacuum pump chain tensioner (hydraulic). you can't mount it on the old-style block, and with the old style spring tensioner, people reported that vacuum pump chain gets stretched almost immediately if you use newer style hpfp

01-15-2018, 10:37 PM	#1
jlegelis Private First Class 33 Rep 129 Posts Drives: 2013 E92 N55 MT MSport Join Date: Jan 2013 Location: Boston, MA iTrader: (0)	HPFP difference between early (2011) and late (2013) N55 E90x engine? Hi All - The rail pressure on my late (2013) N55 E92 is not holding up well under aggressive MHD-based tunes. I've been told the later N55 HPFP pumps don't flow as well as the earlier pumps (I've already upgraded the LPFP - didn't notice any major change). Can anyone confirm, or offer suggestions on how to improve HPFP flow, or perhaps 'downgrade' to the earlier pump if that's even an option? Thx, JohnL Boston 2013 E92 N55
	Appreciate 0 Tweet Quote

01-16-2018, 11:03 AM	#3
Kevin39 Lieutenant 164 Rep 411 Posts Drives: 2011 E90 N55 Join Date: Feb 2016 Location: Indiana iTrader: (0)	Or one of VTTs shotgun kits.
	Appreciate 0 Quote

01-16-2018, 12:36 PM	#5
Turbod Major 396 Rep 1,210 Posts Drives: 2014 E84 X1 35i M Sport Join Date: Mar 2015 Location: Oregon iTrader: (0)	Yes they changed the HPFP. I believe the change was early 2012. The newer style cannot flow as much as the older style. As mentioned above port injection is the solution. A LPFP upgrade is pointless until you add port injection. If you don't want to go port injection then consider a methanol kit. A lot of people ask if you can replace your newer style with the older style, you cannot. __________________ 2011 E92 335i \| 11.7@125 SOLD 2017 Camaro SS \| 12.7@114 SOLD 2019 Audi TT RS \| 10.5@130 SOLD 2020 F97 X3M \| 11.0@123 2023 G80 M3 xDrive
	Appreciate 0 Quote

01-17-2018, 10:40 AM	#12
jlegelis Private First Class 33 Rep 129 Posts Drives: 2013 E92 N55 MT MSport Join Date: Jan 2013 Location: Boston, MA iTrader: (0)	In my car (2013 E92 N55), I'm seeing rail pressure drops on just the stock turbo with an MHD Stage 2+ tune. Do earlier N55's not experience this? Can those cars go to PS1 with stock fueling? p.s. Really trying to avoid going to port injection. This car is a DD and trying to avoid a science project
	Appreciate 0 Quote

01-17-2018, 02:06 PM	#14
FireBlaze Private First Class 67 Rep 143 Posts Drives: 2013 E92 335i 6MT M-Sport Join Date: Mar 2016 Location: Torrance, CA iTrader: (0)	Here's my fuel pump dip on MHD Stg 2+ log: https://datazap.me/u/porschet/log-15...og=1&data=4-17 __________________ VRSF DP, VRSF 7" Intercooler, BMS OCC, Stg 2 LPFP, Custom MHD E30 Tune, Late Model E-Series N55
	Appreciate 0 Quote

01-17-2018, 03:33 PM	#16
jlegelis Private First Class 33 Rep 129 Posts Drives: 2013 E92 N55 MT MSport Join Date: Jan 2013 Location: Boston, MA iTrader: (0)	Here's a 2-3 pull. We've reduced the boost onset a bit in later versions to lessen the dip, but I'm essentially fuel-limited at this point... https://datazap.me/u/jlegelis/wedge-...-31&solo=11-24 FBO E92 N55 2013, with MHD flash and LPFP. Stock turbo. Last edited by jlegelis; 01-17-2018 at 03:44 PM..
	Appreciate 1 Turbod395.50 Quote

01-18-2018, 02:37 AM	#17
juld0zer Lieutenant Colonel 480 Rep 1,600 Posts Drives: Prev 135i 7DCT, Now 130i 6sp Join Date: Jul 2016 Location: 2153 iTrader: (0)	EKPS controls the LPFP. DME controls the HPFP. I haven't dealt with this issue personally but a lot of electrical connectors changed with the newer DME. My guess would be that you just need a male connector to suit the old pump and make up an adapter to suit it.
	Appreciate 0 Quote

04-03-2022, 10:33 PM	#18
2ndgearmoto Registered 0 Rep 1 Posts Drives: 2012 335i Join Date: Apr 2022 Location: Florida iTrader: (0)	I have a 2012 335i with older style hpfp. Engine threw a rod so I swapped a 2013 n55. Both fuel pumps connect to the DME but the newer block's fuel pump has 2 electrical connections where my original pump has only 1. Is there a work around so I don't need new wiring harness and dme/ecu?
	Appreciate 0 Quote