bmwman91 Posted November 19, 2020 Report Share Posted November 19, 2020 The E36X is one of only two solutions on the market with the old-generation Motronic 88-pin connector, and I feel like the Link product is likely the more robust of the two. With the caveat that all wiring and PCLink reconfiguration are my responsibility, is there anything specific about the E36X ECU that would prevent it from being used in a more general purpose way with a car that used Motronic 1.7 (identical physical form factor & connector as M3.3.1, and ~90% identical internal electronics)? I have an E30 318iS with a fully built 2.1L M42 engine, and I have been researching aftermarket engine management options. The M42 is basically a non-VANOS M50 engine minus two cylinders, with effectively the same sensors and actuators from an electrical standpoint. I've rebuilt a couple of M42 harnesses and possess the various extractors and crimp dies needed to properly work with TE/Amp Junior/Standard Power Timer series connectors, so re-configuring the ECU plug is no big deal. It sure would be nice to be able to tune without a hex editor and UV eraser! Thanks! Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 19, 2020 Report Share Posted November 19, 2020 Yeah it sounds like you would be ok. The latest G4X PC Link has a complete pinout for our ecu. Be aware it has ignitors built-in to ignition outputs 1-6 to drive the factory M50 dumb coils, so you will need to stick with dumb coils preferably and you wont be able to use ign 5&6 outputs for anything else when re-pined for a 4cyl (even though the software will allow you to re-assign them to other functions). There is no other special hardware attached onboard so all other IO will work just like our wire-in ECU's. Also note ours doesnt come with a case, it is designed to fit in the OEM motronic case. Not sure if your 4cyl case will be the same. Quote Link to comment Share on other sites More sharing options...
bmwman91 Posted November 19, 2020 Author Report Share Posted November 19, 2020 Thanks. Yeah, the M42 uses "dumb" coils as well, and I am running M52 coils in a COP configuration. I 'scoped the ignition primary signal of my setup, and I was pulling 8A @ 4ms dwell with the Motronic's ignition transistors clamping the flyback to ~420V. I assume that the "igniters" in the E36X are IGBT's that will operate similarly? I don't foresee needing Ign5-6 for anything else, so leaving those de-pinned is fine. M3.3.1 does have a few additional ground connections for stuff like the knock sensor shields and other shields. Are those all just internally tied straight to the main grounds (pins 6/34/55), or is there some noise filtering (ferrite bead, etc) in between? The M42's harness just tied the sensor shields to one of the main ground cables with a splice in the harness. Analog signal integrity is a big priority for how I plan my harness build, so if you recommend that I modify the grounding arrangement of stuff like cable shields to run through the E36X (match the M50TU harness) rather than existing splices in the harness I'll work that into my plans. Have any E36X users mentioned EMI issues on analog signals due to the "dumb" coils? R8 coils fit reasonably well on my engine, and I assume that EMI is significantly less of an issue with those. I'd prefer to stick with the "dumb" coils since the wiring is already there (including shielded cable for the switched leg) and they are screwed down rather than held by friction like the R8 coils, but if your experience indicates that "smart" coils always enable cleaner analog signals then I'll take that into consideration. If the G4X does something like sample the analog inputs whenever there is NOT a spark event, then I suppose it's a non-issue for me. At this point, I think that I'm sold on the E36X as my solution! Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 19, 2020 Report Share Posted November 19, 2020 The ignitors are a specialised automotive inductive COP IGBT. They are rated for 14A continuous @100°C. Our quoted rating in the E36X manual is 10A, so there is a good margin there - possibly PCB track limitations. Clamp is around 400V. I suggest stick with the stock dumb coils if they have adequate ign energy for your cylinder pressure. I have never seen any issues with EMI on these cars with our ECU. R8 coils can be made to work with this ecu but arent ideal due to their high current driver requirement (means you need a strong pull-up or seperate constant current source). If you wanted to upgrade to smart coils in the future I would probably lean more towards a more common low current type like R35 GTR, K20 or IGN1A. You will still need to add a 5V pull-up for these smart coils as per the manual, but more conventional than what you would need to do for the R8 coils. For the shields there is nothing special required. Sheilds can go to sensor ground or power ground, generally no preference, some OEM even use a mixture of both. Pins 28,40,43,44,&45 are designed as sensor grounds, although they are all internally connected to a main common ground plane, but with special routing and filtering techniques to reject noise. Quote Link to comment Share on other sites More sharing options...
bmwman91 Posted November 23, 2020 Author Report Share Posted November 23, 2020 I have placed an order for the E36X through a distributor in my region and am looking forward to a new project. As I have been going over the wiring diagrams for the M50TU, I noticed that it uses a Hall effect cam position sensor, whereas the M42 uses a VR sensor. Can pin 17 (cam signal+) be used with a VR sensor, or were the signal conditioning components stripped out? Based on how the cam VR sensor is connected on M1.7, the other sensor wire just gets tied to ground, so that much is easy to take care of. I have some spare MAX9926's around so it's not a huge deal if pin 17 requires a TTL input, but it'd be cool if it worked directly with a VR sensor. The M42 does not use the "resistor" shield connection on pin 45 like the M50. Is that ground pin filtered the same way as the other ones you listed (or rather, are they all the same/similarly filtered)? The photo of the E36X gives the impression that it is a G4X mainboard attached to a daughter board in the Motronic form factor. Does the G4X board have some of the input/output buffers/drivers removed (for the lines that are not broken-out on either the main or expansion connectors), or are they all there and functionally-available on the dual-row header pins between the boards? Between using the 4 wheel speed sensor signals for TC and some other stuff I want to do, it would be great if the other 4 digital inputs were available for use (since it looks like the G4X XtremeX has 11 DI's, and the E36X makes 7 available). Same deal with the rest of the analog inputs. You can see where this is going. Any info you can provide would be helpful, but I understand if it is outside the scope of "proper" tech support, and obviously any warranty goes out the window. Thanks again. Quote Link to comment Share on other sites More sharing options...
Adamw Posted November 23, 2020 Report Share Posted November 23, 2020 4 hours ago, bmwman91 said: Can pin 17 (cam signal+) be used with a VR sensor, Yes, we call it trigger 2. Set it to reluctor in the software and use the built-in scope later when running to confirm arming thresholds etc are set suitable. Pin 45 is a sensor ground. 4 hours ago, bmwman91 said: The photo of the E36X gives the impression that it is a G4X mainboard attached to a daughter board in the Motronic form factor. Does the G4X board have some of the input/output buffers/drivers removed (for the lines that are not broken-out on either the main or expansion connectors), or are they all there and functionally-available on the dual-row header pins between the boards? Between using the 4 wheel speed sensor signals for TC and some other stuff I want to do, it would be great if the other 4 digital inputs were available for use (since it looks like the G4X XtremeX has 11 DI's, and the E36X makes 7 available). Same deal with the rest of the analog inputs. You can see where this is going. Any info you can provide would be helpful, but I understand if it is outside the scope of "proper" tech support, and obviously any warranty goes out the window. Yes, all our plug-in's use the same "Top board", they all have all of the hardware present including E-throttle controller etc (The only exception is we dont fit the high side drive chip for Aux 5-8 on most it is rare for an OEM to use HS outputs). What IO is available to the end user is typically limited to what the factory applications chose to assign to each pin. We try to discourage any modification to make more IO available as it could become a support nightmare. In many cases though for instance if you wanted E-throttle control in future Link will bring out the correct IO with flying leads for relatively low cost or give you the info to do it if you're not worried about the lifetime warranty. You've probably got enough IO there already for TC, since there is one DI used as a speed input already and 2 DI's for auto trans, then another couple on the expansion. Extra analog and digital inputs can be added via CAN also. Quote Link to comment Share on other sites More sharing options...
bmwman91 Posted November 23, 2020 Author Report Share Posted November 23, 2020 Great, that is enough info to keep my plans going while I wait for the ECU and a spare harness to build up. And yes, if at some point it is an option to get a pinout diagram for the board-to-board header so that I can solder leads as-needed, it would be much appreciated. We'll see if that is needed...I am not running A/C either, so that buys me a couple more inputs. CAN expansion for things is a good idea as well, so I'll have to see what options are on the market. I'll probably post a build thread in the Customer Vehicles subsection once I get things going. If I do end up soldering things / making modifications to the hardware, is there any issue with posting details about that, or does Link prefer not to have people encouraging that? I don't mind leaving those details out. Quote Link to comment Share on other sites More sharing options...
bmwman91 Posted December 29, 2020 Author Report Share Posted December 29, 2020 I am finalizing my wiring diagrams and preparing to start constructing the modified OEM harness. Just as a sanity check, ALL pins listed as "nc" in the Quick Specs are internally floating and not connected to anything at all, correct? Thanks again. Quote Link to comment Share on other sites More sharing options...
Adamw Posted December 29, 2020 Report Share Posted December 29, 2020 Yes, NC means not connected. Quote Link to comment Share on other sites More sharing options...
bmwman91 Posted January 1, 2021 Author Report Share Posted January 1, 2021 Cool, just making sure (a little helping of paranoia has never hurt when it comes to wiring plans). With that being the case, I assume that I can completely remove the constant 12V wire from position 26 (the spec sheet lists it as "nc (Constant 12V)"? I've started roughing-in some of the new wire runs and reorganizing / untangling the remaining original wiring. I have to say that I am now a big fan of Tefzel insulated wire...expensive, but the smaller OD is super helpful, and the smooth surface finish combined with its surprising rigidity makes it a heck of a lot easier to feed through PVC sheath tubes (not pictured). The original wire that BMW used is perfectly good considering it has not cracked or deteriorated in 30 years, but the PVC insulation leaves a bit to be desired (or at least I think it is PVC). Anyway, happy new year. I am pretty excited to get the car going on the E36X in 2021! It's probably about time that I made a build thread in the proper section... Northern 1 Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 3, 2021 Report Share Posted January 3, 2021 On 1/1/2021 at 7:33 PM, bmwman91 said: I assume that I can completely remove the constant 12V wire from position 26 (the spec sheet lists it as "nc (Constant 12V)"? Correct, our ECU doesnt use that. Quote Link to comment Share on other sites More sharing options...
Smwoodward Posted January 31, 2022 Report Share Posted January 31, 2022 On 1/3/2021 at 1:49 AM, Adamw said: Correct, our ECU doesnt use that. Is there a way to get the header pinout for the ecu board? Quote Link to comment Share on other sites More sharing options...
Vaughan Posted January 31, 2022 Report Share Posted January 31, 2022 This is the pinout of the ECU to body loom header, it is available in the PCLink help manual and in the quick start guide for this plugin ECU. Quote Link to comment Share on other sites More sharing options...
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