Hello,
I have been working for sometime on figuring out how to make N54-powered cars easier to own and maintain. I currently own a 2008 E61 that I got at the end of last year, but this would be my third N54-powered car in the last 13 years. As I'm sure most of you know, some of the most aggravating issues of the N54 are related to the DI system. It seems to be the case that HPFP issues have been sorted by BMW in later revisions of the pump. Our fuel injectors, however, still need considerable attention considering how common it is for them to leak. I know how a $2.5K initial investment for lifetime injectors using one of the two vendors we know of may be reasonable for some, but I am not sold on this path. Which brings me to what I am currently working on right now:
I decided to find a way to run Bosch HDEV 5.2 solenoid direct injectors (the ones on the N55 and newer BMW engines) and this is what I came up with:
1. The injector bore on the N54 is about 1mm smaller at the top than it needs to be to accommodate for the HDEV injectors. The bore would need to be increased to about 21mm at a depth of at least 27mm from the piezo solenoid decoupling element seat. I am actually going for about 33mm depth because I am adding a 5mm 6061 aluminum washer to the bottom of the newly drilled bored so that the HDEV injector decoupling elements can sit properly (the decoupling element on these injectors are smaller than those on the piezo injectors). I took the head to machine shop to have it resurfaced and to increase the bore on the injector holes. I know very little about machining terms, pardon any misuse here.
2. The most difficult part is figuring out how to run the damn thing. I could get a Delta GDI6 and call it a day, but I wanted something that would integrate better with my E61, while also giving me the chance to work on something fun while going to school. So, I decided to design my own ECU and make it opensource. My primary intention was to build an ECU that can run my Frankenstein's N54 while also giving me the ability to avoid some of the BMW idiosyncrasies. So, here's what the prototype ECU is offering at the moment:
6x direct solenoid injectors
6x port injectors
Support all the engine-critical sensors and actuators found in the N54/N55/S55/B58/S58
Support for 2x EWGs (in case I find an S55 laying around somewhere)
Support for dual HPFPs
Bluetooth and GPS modules
Data logging through USB, limited on-board data logging
2x wideband and 2x narroband sensors
2x LIN/BSD interfaces
2x FDCAN interfaces
Diagnostics for every input/output
My main constraints for the ECU are: 1) the board components need be to as inexpensive as possible ($175-$250 per board without enclosure or header for an order of 5), 2) the components need to be readily available at LCSC given that I will be using JLCPCB to print the PCB. The ECU is is powered by the STM32H743IIT6 MCU, uses the NXP MC33PT2000 from NXP for DI control, and Molex Compactus 186-pin connector. I want to run it barebones eventually, but I think branching out the rusEFI project may be the proper start for the project. It has taken my a while to design the PCB. My first design was based on the Core8 ECU designed by a guy named Ben from the UK/Lithuania. Adding DI, EWGs, BT/GPS, and LIN/BSD has forced me to reinvent the PCB a few times. I should have the PCB files available online in the next month or so.
I will be posting pictures of the work as I move forward with the project. I would appreciate your feedback, specially on the features of the ECU, as this is my first time building something like this.
I have been working for sometime on figuring out how to make N54-powered cars easier to own and maintain. I currently own a 2008 E61 that I got at the end of last year, but this would be my third N54-powered car in the last 13 years. As I'm sure most of you know, some of the most aggravating issues of the N54 are related to the DI system. It seems to be the case that HPFP issues have been sorted by BMW in later revisions of the pump. Our fuel injectors, however, still need considerable attention considering how common it is for them to leak. I know how a $2.5K initial investment for lifetime injectors using one of the two vendors we know of may be reasonable for some, but I am not sold on this path. Which brings me to what I am currently working on right now:
I decided to find a way to run Bosch HDEV 5.2 solenoid direct injectors (the ones on the N55 and newer BMW engines) and this is what I came up with:
1. The injector bore on the N54 is about 1mm smaller at the top than it needs to be to accommodate for the HDEV injectors. The bore would need to be increased to about 21mm at a depth of at least 27mm from the piezo solenoid decoupling element seat. I am actually going for about 33mm depth because I am adding a 5mm 6061 aluminum washer to the bottom of the newly drilled bored so that the HDEV injector decoupling elements can sit properly (the decoupling element on these injectors are smaller than those on the piezo injectors). I took the head to machine shop to have it resurfaced and to increase the bore on the injector holes. I know very little about machining terms, pardon any misuse here.
2. The most difficult part is figuring out how to run the damn thing. I could get a Delta GDI6 and call it a day, but I wanted something that would integrate better with my E61, while also giving me the chance to work on something fun while going to school. So, I decided to design my own ECU and make it opensource. My primary intention was to build an ECU that can run my Frankenstein's N54 while also giving me the ability to avoid some of the BMW idiosyncrasies. So, here's what the prototype ECU is offering at the moment:
6x direct solenoid injectors
6x port injectors
Support all the engine-critical sensors and actuators found in the N54/N55/S55/B58/S58
Support for 2x EWGs (in case I find an S55 laying around somewhere)
Support for dual HPFPs
Bluetooth and GPS modules
Data logging through USB, limited on-board data logging
2x wideband and 2x narroband sensors
2x LIN/BSD interfaces
2x FDCAN interfaces
Diagnostics for every input/output
My main constraints for the ECU are: 1) the board components need be to as inexpensive as possible ($175-$250 per board without enclosure or header for an order of 5), 2) the components need to be readily available at LCSC given that I will be using JLCPCB to print the PCB. The ECU is is powered by the STM32H743IIT6 MCU, uses the NXP MC33PT2000 from NXP for DI control, and Molex Compactus 186-pin connector. I want to run it barebones eventually, but I think branching out the rusEFI project may be the proper start for the project. It has taken my a while to design the PCB. My first design was based on the Core8 ECU designed by a guy named Ben from the UK/Lithuania. Adding DI, EWGs, BT/GPS, and LIN/BSD has forced me to reinvent the PCB a few times. I should have the PCB files available online in the next month or so.
I will be posting pictures of the work as I move forward with the project. I would appreciate your feedback, specially on the features of the ECU, as this is my first time building something like this.
