EWP Control strategy

[Dumaurier7]

Good day all, anyone have information on the control strategy used for the EWP, any information will be appreciated. After further thought I think I should give some more detail and context here, I am presently doing an N55 build using a pair of upgraded Big Boost twins. I was advised to switch over to an S55 DME in order to get the dual electronic WG's and dual bank wideband controls to work (by cloning the ISN from the N55 DME to the S55 DME, my only question thus far is controlling the EWP on the N55. I have since looked at its wiring which turns out to be basic, the single control wire (violet) goes back to pin #26 on the connector. I am wondering if I will be able to move this over to an open pin slot in the appropriate connector of the S55 DME and have the functionality coded in, anyone know if something like this is possible?

 

[fstbtstr]

I think it might require lots of work, since you already have an S55 DME, you can probably find some aftermarket mechanical water pump and mount it in the stock water pump location, will probably need to fabricate some brackets and use different serpentine belt.
Or use an aftermarket electric water pump and make it always run/control it in the same way it's done with aftermarket electric wps for chevy sbc

 

[wheela]

I know you already bought the s55 DME, but I recently saw on another forum that the n55's they put in the Alpina B3's were actually twin turbo n55's. I'm not sure if it's still the same family of Bosch DME, or if there were any electronic wastegate versions of the alpina n55, but it may be worth looking into.

 

[Dumaurier7]

I already bought the one for the S55....... after fitting the harnesses, I am confident that it will work as both the DME's are the same along with the sensors and the connectors, the pin locations for the main (cam, crank, boost) sensors are also the same. The only thing I am not sure about is the EWP as the S55 never had one but because it does have an auxiliary pump for the turbos it's an option for me to hijack the signal and use it to control the EWP, I am just not sure how the Aux. Pump is controlled so I won't be sure how the EWP will work, I don't want to have overheating problems. Mods, please move this thread to the coding section thanks.

 

[Dumaurier7]

I had an encouraging discussion with a forum member who knows about this stuff, he said the following

" Well, after a quick look at the S55 documentation it seems that the DME is very similar.

You have the electronic water pump control on pin 246, 256 and 241 and it is marked as being "N55 only". It looks like that is just the BSD connection to multiple devices so probably already connected.

Looks like we have the IBS, electronic water pump, alternator and glow plug relays all on the BSD bus. But looking at the control strategy of the water pump there is a bit called "SY_BSSWP - System-constant BSS water pump installed import 1". This looks to be set to a value of 1 which means it should already support a water pump connected on the BSD.

Have you tried to connect the pump yet? I'd be interested to see what happens if you just hook it up onto the BSD."

If this does not pan out, I found a great little controller with great capabilities at a reasonable price to control the pump independently .

 

[Dumaurier7]

For the N55, the sub harness for the water pump has two lighter gauge control wires (red with green and the other violet) and two heavier ones for power and ground., the power wire cis supplied by the power control module and the ground wire attaches to the engine block.
In the S55 harness connector the location for both control wires was left unused and (obviously) the cables for powering the pump are not there. For the N55, the 12v trigger for the starter is incorporated in this harness as well; to keep it simple I de-pinned this harness from the N55 and installed it in the S55 one, I also installed the control wires in the same locations (as the N55) so hopefully it will work as hoped.

……. Here you can see both wires, I haven’t inserted them yet! I’m waiting until the last minute in case something changes.

 

[Ali_X]

Hi, there,

Do you have any news? Did it work?
Did you get the dual HPFP to work?

Do you think it is possible to use the DME of the N55 on an S55 swaper engine to keep the Xdrive and make the car believe that the N55 is still present or you can put the DME of the S55 and it will have no impact on the Xdrive and the ZF8HP gearbox?

Thank you in advance

 

[Dumaurier7]

Hi, I can’t answer any of those questions yet as my motor and car are still in pieces, however because of the similarities between the N and S55 engines I do not anticipate any problems. The x drive factor I cannot comment on as my car isn’t one, as for the transmission, after close inspection of the transmission harness I found that the DME switches power to the it and connects it to the CAN BUS, all the pins are the same as well so I don’t anticipate any problems with my ZF………but if the ZF decides otherwise I’ll upgrade to a DCT from an M2 Comp to ensure that there are no problems.

 

[Ali_X]

Hi,

Thank you for your feedback. When the engine is assembled and installed, don't hesitate to let us know.

On my side I plan to do the opposite and mount the S55 with the DME of the N55 the solution to try to activate the dual fuel pump with the DME or use a controller is very interesting, I think that if it does not work, then I would try to put a B58 TU pump (if compatible with) that will be controlled natively by the DME of the N55 and make a custom map to adapt the fuel supply.

If you have any advice, don't hesitate.

 

[Dumaurier7]

Or you can buy my vacuum pump and Nostrum/ Precision big bore high pressure fuel pump kit!

 

[Ali_X]

Hahah yes indeed, but I'd really like to get the dual pump working to get as close as possible to OEM!

 

[Dumaurier7]

Not trying to to dash your hopes but a couple people have tried before but weren’t able to get it to work right, do a search here and you’ll see, sometimes the juice just ain’t worth the squeeze!

 

[Ali_X]

Hi,
thank you for your pragmatic point of view, I'm continuing my research and I found this interesting discussion about a person who says he managed to make the double HPFP work with an N55 DME:

Fitting a S55 fuel system to my f series N55 EWG

Fitting a S55 fuel system to my f series N55 EWG

f87.bimmerpost.com

 

[CalvinNismo]

Hi,
thank you for your pragmatic point of view, I'm continuing my research and I found this interesting discussion about a person who says he managed to make the double HPFP work with an N55 DME:

Fitting a S55 fuel system to my f series N55 EWG

Fitting a S55 fuel system to my f series N55 EWG

f87.bimmerpost.com

There is also this thread to have a look at.

M135i N55 EWG retrofitting S55 high pressure fuel pump

Hi everyone, Before getting into the topic, I'd like to give some background about myself, I live in Belgium, I am just a car enthusiast who does a lot of track days and driftdays, I don't have any mechanical background nor tuning knowledge. Every knowledge that I have now regarding tuning is...

www.spoolstreet.com

 

[Dumaurier7]

Good luck!