=jon= Posted August 5 Share Posted August 5 Hi All I've done some searching, but not sure of the answers... I've got MS3x up and running with EDIS. Previously it was MS2, and I *think* at build was modified to support EDIS. I'm looking to drop EDIS and run the coils direct (either with an external ignitor or swap to coils with one built in). Mainly so I can look to run LPG directly from the MS3x (via a P+H driver) rather than needing a secondary ECU. Does anyone know what mods I will need to do/undo (if any) to connect the crank sensor direct to the MS instead of the PIP/SAW? I can take pics of the board if needed to show what's there currently. Also any thoughts on running an external ignitor with the EDIS coils vs. something like VAG coils - as I am upgrading an existing setup not starting fresh is there any benefit? Thanks! Jon Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted August 6 Share Posted August 6 Pics of the board(s) would help, although the MS3 is a proper dog's breakfast to get apart Use VAG coils with the built-in igniter for an easy life, trying to cram that stuff inside the ECU next to the sensitive electronics is a real PITFA. You WILL need to modify the ignition input circuit - if you are lucky it's built with the VR input components in place and you just need to move 2 jumpers, if not it will need that circuit adding. You most likely WILL need to add a coil driver circuit and some wires inside to give you 4 spark outputs too, again it depends how yours was built. I have daughterboards that do this for MS1/MS2 I don't know if they'd fit inside an MS3 with all the other nonsense going on inside the case. Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted August 6 Share Posted August 6 15 hours ago, =jon= said: I'm looking to drop EDIS and run the coils direct (either with an external ignitor or swap to coils with one built in). Mainly so I can look to run LPG directly from the MS3x (via a P+H driver) rather than needing a secondary ECU. It'll leave you with a tidier install that doesn't rely on parts that are getting hard to source - so don't let me put you off - but you don't need to lose EDIS to do this. You just need ignition table switching when you change fuel. The EDIS knows nothing about it, it just obeys the timing signal it's getting from the Megasquirt. In theory I had exactly this with a Megasquirt 1/EDIS years ago. I hadn't got the table switching working by the time I sold the vehicle, think I'd damaged the table switching input. @FridgeFreezer, was this ever sorted? Quote Link to comment Share on other sites More sharing options...
=jon= Posted August 6 Author Share Posted August 6 Thanks - I think I have some pics of the board somewhere already, lemme see if I can find them... If I was to go with an external ignitor, it would be outside of the case - something like one of the Bosch external ignitors that can be run in the engine bay. It's already running dual fuel with a table switch and an external LPG ECU (which intercepts the existing petrol injection signal) - I was going on some comments from ExtraEFI about running secondary injectors on the MS3X: Quote but if you have a true EDIS setup (12 pinned EDIS8 device) it won't run an MS3X setup as they give no angular input to the MS ECU. You would need to run the ECU directly off the trigger wheel. Which suggests that I need to swap over to use two 'true' sets of injector drivers... @HoSS built the ECU I believe, so maybe he can remember how he built it, although it was a loooooong time ago... Quote Link to comment Share on other sites More sharing options...
=jon= Posted August 6 Author Share Posted August 6 Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted August 6 Share Posted August 6 Right, that photo is an MS2 not an MS3 - it has the EDIS mods and it has the VR input circuit, but no coil driver circuit. Have you fitted an MS3 upgrade to it since that photo? I don't know what you've been told about running 2 sets of injectors but unless you are trying to do sequential injection (which is pointless anyway) MS1/2 does not need to know the crank angle at all any more than a carburettor needs to know the crank angle... MS3 may be different, it should NOT matter for this but they've made the thing so over-complex now I don't know WTF it does or doesn't need. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted August 6 Share Posted August 6 MS3 will run with or without a cam signal -with means you can do more obviously, but not that critical. Perhaps, as I have read at some point, LPG doesn't like hanging about in the plenum too long, so the want/need to run sequential comes from there. Quote Link to comment Share on other sites More sharing options...
=jon= Posted August 6 Author Share Posted August 6 That pic is back from when it had the MS2 board on it - that board was swapped with the MS3 board a while back but no other changes were made. If it's got the VR input, the swapping to run the crank sensor directly should be fairly straightforwards - rewire the sensor and swap the jumper? I'm not sure of the validity of the crank angle comment - it was Phil Ringwood at ExtraEFI who made it, and he seems to know his stuff. It seemed to be a suggestion that to use the MS3 injector outputs it needs the angle (maybe it's an MS3 specific limitation for the extra outputs?). For the coil drivers, MS3 has 8 of them built in (assuming that they work!) Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted August 6 Share Posted August 6 If MS3 can't run without crank angle then they've f***ed it up worse than I thought. You can't run *sequential* without crank angle but as I said, that's largely pointless anyway, manufacturers do it for emissions and only at low RPM. For the VR input, yes just swap the VRIN/OPTOIN jumper in the bottom corner of the board near the D37 and then the OPTOUT/VROUT jumper hiding under the mess of red wires... although I notice U7 is missing and that's an op-amp that's critical to the VR input circuit so you'll need one of those. I probably have one I could post you. Quote Link to comment Share on other sites More sharing options...
=jon= Posted August 6 Author Share Posted August 6 I may have a play with the MS3 and see if it will run secondary injectors from EDIS - I have the looms etc so it should be easy (in theory) to test. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted August 6 Share Posted August 6 from EDIS? You could go old school and just relay the supply side to the injectors, just one per bank. Quote Link to comment Share on other sites More sharing options...
=jon= Posted August 6 Author Share Posted August 6 With EDIS as the trigger source is probably what I meant... Running it via relay could be another option, yes. I really need to check if the external peak & hold driver (AEM) that I have acquired will actually drive the LPG injectors first - from what I understand some don't work on the same 4A/1A currents as petrol injectors, so the whole plan to ditch the LPG ECU may be a non starter anyway... Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted August 6 Share Posted August 6 Correct, most are low impedance. Quote Link to comment Share on other sites More sharing options...
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