M106 MS help / question

[JackNC]

Hi all, I'm (meaning my local shop) in the middle of swapping an M106 into my 86 535 5 speed. My initial goal was to keep it as close to stock m106 as possible until I get a little more familiar with the engine and come up the turbo learning curve. I did upgrade the wastegate to a Tial, as I've read how problematic and limiting the stock wastegates can be. I know about the stock turbo limitations and may upgrade that eventually as well. After many unsuccessful attempts to get the original 745 DME working, I've decided to go with Megasquirt. Presumably MS2 PNP. I'm talking to a local (Raleigh) tuning shop and to DIYAutotune to confirm an MS2 will work for my goals (strictly pleasure/street, no racing or crazy high HP).

Assuming the MS2 is indeed the right choice, I'm having some difficulty getting a complete list of what else is required to make this work in the E28. I already have the Condor E28 to M106 harness adapter installed, so I'm assuming no further harness customization needed? I know the low imped injectors need to get replaced with high imped and have some of those already. I've also read and been told that I'll need a 60-2 crank trigger wheel. (If anyone has an extra they are trying to get rid of, I'm interested).

Aside from these items, what else is needed to implement MS2 with the close to stock M106? Down the road I can consider other upgrades like wasted spark, upgraded fuel system, etc. For now, I'd just like to get it running well close to stock.

I've tried to read and search as much as I can on this topic, including the Turbo FAQs. If you know of a thread I missed that has the M106 swap details summarized, I'd appreciate knowing where it is.

Also, if anyone near Raleigh has swapped an M106 into an E28, that would be great to know.

Thanks in advance.

[turbodan]

60-2 wheel is the biggie. MS can use either high or low impedance injectors, it's just a matter of configuration. If I remember correctly it's a software setting. Alternatively you can source some 30lb injectors that will support 330+ rear wheel or some 42's that will support 400+.

MS is s good choice and I can provide some very good baseline settings for some of the more challenging features. High boost and big power are no problem, standalone EFI removes the most significant obstacle on that path.

[JackNC]

Dan, thanks for the quick reply. Do you know if the MS2 will work with the E28 b34 harness (matched to M106 loom with adapter)? I'm asking the folks at DIYautotune and Condor but they aren't sure whether the MS2 will fit with this harness setup or I'll need to go back to all b34 harness or a custom harness.

Thanks

[turbodan]

I believe the only plug and play option is a b35 harness. Three row connector with 55 pins. I don't think any are available for the older motronic versions since none of them have the other hardware provisions for MS.

[JackNC]

Thanks Dan. After a lot of research, it appears there aren't any real Plug N Play standalone ECUs for the 35 pin harnesses. At least as best I can tell. I've seen some references to 55 to 35 pin adapters but nothing recently available. Are you aware of any other ECU makers who make a 35 pin unit? I'd rather not switch harnesses. Thanks.

[turbodan]

I think you would have to build something. A custom motronic DME with ms2 guts. The wiring would be between the ms2 db37 connector and the back side of the existing dme connector. You would have to wire in the vr sensor additionally, or utilize the existing speed or reference sensor connections, assuming there is enough length available to reach. The m20b25 crank sensor has quite a bit of lead on it so you could probably use one of those.

If you can solder and sort through the ETM it could be done in an afternoon. Which DME is in it now? The 059?

[JackNC]

Thanks, custom building MS2 in Motronics case is where I'm leaning right now. After the m106 DME that came with the M106 motor turned out to be bad, we tried the car's original 059 DME and the M106 motor (without turbo connection) fired right up no problem.

I'm trying to reach out to Peter Florance to see if he or someone he recommends can custom build the MS2 in a Motronics case. Do you know anyone else who does this type of custom MS2 in a Motronics 35 pin case build?

Thanks for all the help!