Miocrosquirt access board
#8
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I guess my biggest question would be why you want to mess around with any kind of external breakout board at all?
Given the stated goal of doing "a clean install," my instinctive reaction is that a standard MS2-3.0 build, plus either the P&H board or the 4 channel driver board (if you don't plan on low-impedance injectors) would be an absolutely ideal solution. Either of the two daughterboards will fit into the stock case, and with the addition of a second connector on the endplate (such as a DB-15 or a Molex 062 or Mini-Fit Jr) you can then build a simple harness to plug the MegaSquirt box into the vehicle's wiring harness (assuming you can find a source for the correct Motronic connector.)
If you're planning to re-wire the car anyway, then it's even simpler.
Either way, I don't see how a Microsquirt Access Board or a regular MS Relay Board simplifies the situation at all. To the contrary, it just adds bulk, exposed wiring, and points of failure.
Unless I'm missing something which seems obvious to people who work on Mercedes.
Nice looking crank-trigger setup, by the way. Always wished I could have figured out how to do a behind-the-pulley setup with mine.
Given the stated goal of doing "a clean install," my instinctive reaction is that a standard MS2-3.0 build, plus either the P&H board or the 4 channel driver board (if you don't plan on low-impedance injectors) would be an absolutely ideal solution. Either of the two daughterboards will fit into the stock case, and with the addition of a second connector on the endplate (such as a DB-15 or a Molex 062 or Mini-Fit Jr) you can then build a simple harness to plug the MegaSquirt box into the vehicle's wiring harness (assuming you can find a source for the correct Motronic connector.)
If you're planning to re-wire the car anyway, then it's even simpler.
Either way, I don't see how a Microsquirt Access Board or a regular MS Relay Board simplifies the situation at all. To the contrary, it just adds bulk, exposed wiring, and points of failure.
Unless I'm missing something which seems obvious to people who work on Mercedes.
Nice looking crank-trigger setup, by the way. Always wished I could have figured out how to do a behind-the-pulley setup with mine.
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#11
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Ben is apparently reading my mind. I'd meant to say that, but it escaped me.
To put it bluntly, EDIS is a crutch, and in my opinion, not a very good one. With a Megasquirt, it merely adds complexity to the situation. Your best bet is to wire the VR sensor directly to the MS, and set up the MS to drive the ignition coils directly.
If you find yourself running low on output ports, I recently discovered a relatively new gadget called the I/O extender. It's a daughterboard for the MS2 which contains an on-board uC, and gives you four VR conditioners, six high-current drivers, six general-purpose logic-level I/O ports, and 8 ADCs.
Woot!
Info:
I/O Extender Board v1.0 for M2/Extra
jbperf.com • View forum - I/O Extender
To put it bluntly, EDIS is a crutch, and in my opinion, not a very good one. With a Megasquirt, it merely adds complexity to the situation. Your best bet is to wire the VR sensor directly to the MS, and set up the MS to drive the ignition coils directly.
If you find yourself running low on output ports, I recently discovered a relatively new gadget called the I/O extender. It's a daughterboard for the MS2 which contains an on-board uC, and gives you four VR conditioners, six high-current drivers, six general-purpose logic-level I/O ports, and 8 ADCs.
Woot!
Info:
I/O Extender Board v1.0 for M2/Extra
jbperf.com • View forum - I/O Extender
#12
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Oh, RdSnake, one other thing- You'd mentioned a desire to go full sequential eventually. To do this, you will need a second trigger off of one of the cams, giving you exactly one pulse per camshaft rotation (or more importantly, one pulse for every two crankshaft rotations, which is one complete engine cycle.)
Wasn't sure if you were aware of this already.
Wasn't sure if you were aware of this already.
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The cars dont have Motronic. They came fitted with CIS injection. It is absolutely important for me that no hacking of the factory wiring is done. I want to be able to reverse the MS conversion if I decide that I want to. The MS installation is going to be a parallel install with no intertwining with the factory wiring and thats what I meant by doing a clean install. Again, it is absolutely important that I preserve as much of the originality of the car as possible. I just cant live with the CIS injection anymore.
My last MS-II install, my miata, was 3 years ago and Im a bit rusty with the details and all.
For me, EDIS is a simple install and because Im familiar with it, I know I can get it up and running in no time. Im very happy with the EDIS system on my miata. I will eventually convert to sequential but that will come after I figure out a way to add CMP signal either via a camfshaft trigger or a custom trigger that I will put inside the distributor.
One car will be converted to ITB's while the other one will remain "stock".
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My last MS-II install, my miata, was 3 years ago and Im a bit rusty with the details and all.
For me, EDIS is a simple install and because Im familiar with it, I know I can get it up and running in no time. Im very happy with the EDIS system on my miata. I will eventually convert to sequential but that will come after I figure out a way to add CMP signal either via a camfshaft trigger or a custom trigger that I will put inside the distributor.
One car will be converted to ITB's while the other one will remain "stock".
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#14
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Sounds like there's no clear path on the cam sensor at the moment, which actually isn't a horrible thing. You can obviously run without one, though you won't be going sequential. In all honestly, sequential injection is more about idle emissions than anything else- you're not going to see any power gain. That fact alone would further simplify the build a bit, as the regular 3.0 board would suffice with no daughterboards. You could even run an MS1 CPU instead of an MS2 if cost is a major factor, or if you're more comfortable with its rather simpler design.
For me, EDIS is a simple install and because Im familiar with it, I know I can get it up and running in no time.
Are you planning to retain the distributor as a functional item, or is a distributorless ignition (either a Miata style wasted-spark system or COPs) a part of the picture?
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Rd, I'd go with the MS2 V3.0 with the 12' long wiring harness. I'd opt to not use the EDIS control box, but would still use the trigger wheel, VR sensor, and coils. You'll need to add 2 BIP373s to the ECU. Wiring labor would essentially be identical to using the EDIS box, but you've removed its unneeded complexity. I think you'd still have a really well thought out and clean installation, actually I think it would be cleaner. The EDIS coils themselves are cheap, fairly hot and require a short dwell time, so they'd do great in a wasted spark set up like this.
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Ok, that last response could have been more thorough. ![big grin](https://www.miataturbo.net/images/smilies/biggrin.gif)
Article 1: By "flashing", we are describing the process of loading new boot code, not merely of loading new maps. IOW, it's not something you do often.
Article 2: This is only a problem when you are running coils which use a +5 logic-level trigger, and at that, only when you have configured the coil driver outputs of the MS in the old-fashioned style. Here is a writeup which describes a better design, which alleviates this problem: https://www.miataturbo.net/forum/t33964/
Article 3: If you use coils without internal igniters, and drive them directly with BIP373s as Ben suggests, then this is also a non-issue. Personally, I prefer not to do it this way to keep noisy, high-current stuff out of the MS, but to each his own.
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Article 1: By "flashing", we are describing the process of loading new boot code, not merely of loading new maps. IOW, it's not something you do often.
Article 2: This is only a problem when you are running coils which use a +5 logic-level trigger, and at that, only when you have configured the coil driver outputs of the MS in the old-fashioned style. Here is a writeup which describes a better design, which alleviates this problem: https://www.miataturbo.net/forum/t33964/
Article 3: If you use coils without internal igniters, and drive them directly with BIP373s as Ben suggests, then this is also a non-issue. Personally, I prefer not to do it this way to keep noisy, high-current stuff out of the MS, but to each his own.
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In all honestly, sequential injection is more about idle emissions than anything else- you're not going to see any power gain. That fact alone would further simplify the build a bit, as the regular 3.0 board would suffice with no daughterboards. You could even run an MS1 CPU instead of an MS2 if cost is a major factor, or if you're more comfortable with its rather simpler design.
I'd reccomend going for sequential injection if you have the time/inclination etc.
#20
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