MS3X build thread

[akluminus]

The car was running fine, but it was time to start to switch over to a new MS3X ECU.. on the path to boost!

My car is a 1984 633Csi, and I am not planning on switching the wiring harness out. So for those that may be interested, this will be how to get an m30b32 with a motronic 1.1 wiring harness up and running on MS3X. Some parts of the megasquirt sticky were out of date or didn't apply to this setup, so hopefully this info will help someone at some point down the road.

First up was picking up most of the needed parts:
- MS3X Expansion V3.57 (assembled). Didn't want yet another project so I bought a complete kit and the 12" breakout leads (diyautotune.com)
- GM temp sensor (diyautotune.com)
- 60-2 tooth wheel and VR sensor, throttle position sensor (forum members, thanks!)
- Dead 35pin motronic ecu
- 60lb siemens deka injectors

I also picked up a wideband O2 sensor, but it won't be used until the car is running somewhat decently. I don't feel like dumping fuel all over it in the process.

6 pin TPS. Will have to run a few new wires for it.


Newer VR sensor and trigger wheel. Took me a while to realize the new bracket would work fine if I mounted it in a different set of holes. Almost accidently fabricated a new bracket. The sensor position hasn't been adjusted yet or tested for clearance.


And the new injectors:


With all the sensors installed, I ripped apart the old ECU and trashed the motronic internals. Even with most everything on the MS3X already, I decided to use the internals of the ECU case primarily for prototyping area (even though that shouldn't be more than an occasional resistor/diode).





The prototype boards came from amazon:
http://www.amazon.com/gp/product/B00B67 ... UTF8&psc=1

Once trimmed down on the edges, it fit nicely into the case. The backside of the board is secured with small standoffs.



If you plan to do something similar, I'd highly recommend a desoldering gun. You can use a manual solder sucker, but this tool makes quick work of removing the connector from the old circuit board:
http://www.amazon.com/Hakko-808-KIT-Con ... B00FZPTEK2

More to come...

[scoobydo]

please do keep us updated on this. I have a 333i turbo running Zytek management but may look to go MS as it is a bit of a pain for mapping as I don't have the breakout box. So majority of the work is done and I can interpolate the zytek settings for fuel an timing but not sure about CPS. The 333i used the flywheel Sensors speed and position,the front of the engine has a sensor diagnostic only when it was on the original motronic. Not sure if I need to change the damper or whether how the Zytek calculates the position is suitable. Going to have a poke around on the car today.

[akluminus]

My schedule on car stuff is pretty slow...

I have some more pics and updates to share soon, trying to get it fired up right now. Does anyone have a .msq file for a running m30 that came from a newer megasquirt 3, like the 3.57 board?

Aaron

[akluminus]

After many tweaks and changes, it is up and running. Here is a pic of the final case setup.





In the end I'm not sure this was worth the hassle. It is the 35 pin motronic, so I ended up having to run a bunch more new wires anyway. The extra DB25 on the side is for logic spark, fuel pressure sensor, TPS, and Idle (my e24 had idle lines going to a separate idle control computer).

I'll post the wiring pinout next.

[akluminus]

The MegaSquirt FAQ was a great start, but it is also about 4-5 years old and some of it isn't applicable if you end up with a newer unit like mine (ms3x 3.57 prebuilt). Here are the biggest changes/differences I found.

- MS3X 3.57 prebuilt (I'll just call in prebuilt from now on), can drive 2 and 3 wire idle control valves directly. Use the FIdle output.

- The prebuilt doesn't have the ignition coil driver (BIP373, this kit: http://www.diyautotune.com/catalog/bosc ... p-230.html). You have to buy it separately and mod the ECU. This was pretty annoying since I didn't discover it right up until I tried to start. I put it in my prebuilt kit, but ended up not using it in favor of a single LS-1 coil driven by the MS3X logic spark output A. Still have the distributor for now, and a pile other LS1/LS2 coils for later.

- There is an extra switched 12V input on the 35 pin motronic for my e24 (18). Some places show this as always-on 12V, but I was able to use it to power the LC-2 wideband nicely.

- The prebuilt is setup for VR input and, other than a 10K resistor per other posts, didn't need any adjustment. I have the sensor about 1mm away from the toothed wheel.

- Prebuilt tach output on the MS3X drove the tachometer just fine, thankfully

Other things that may help:

- The latest firmware doesn't seem to care if you have your TPS wired backward. I don't think I'll bother switching the +5V/GND lines on it since it works well. TunerStudio will warning you about the fully open value being smaller than the fully closed, but it works.

- I'm using the stock 2 wire idle control valve. Still sorting out the correct settings, but it appears to operate in inverted mode (applying voltage, or increasing the PWM amount) closes it.

- I disabled the priming pulse. You end up doing a lot of a ignition on / ignition off tests while making changes, and this quickly just results in a flooded car.

- I blocked off the cold start valve on the intake manifold, and to plug the extra port on the fuel rail I used a fuel pressure gooahj.

- My temporary intake setup used a short piece of 3" aluminum tube to connect the idle air input and the new air intake temp sensor. This significantly heatsoaked pretty quickly resulting in a very lean condition. I actually ended up jambing the IAT into the end of the cone filter, which helped significantly since it both isn't above the hot engine and also mounted in rubber instead of something that conducts heat better.

- I bought 60lb siemens deka injectors for this, and the flow tests that came with them had the injector dead times - very usefull since the default settings of .75ms resulted in about .4ms of extra fuel.

I'm still a bit unclear on the 60-2 wheel ignition settings. What little information out there seems to be conflicting. Mine runs well with input capture on falling edge with a tooth #1 angle at 82.5. If I swapped polarity on the VR sensor AND switched to rising edge, wouldn't I just be back to where I started? Anyway, this may actually need to be 84 degrees instead of 82.5 - when verifying with an advanceable timing light, I'm looking at the mark from the side so I can't easily tell if it is 100% on top or not. Attempting to switch it to rising edge doesn't work at all. My tooth logs look solid. When set to a fixed 10 degree advance for verification though, it does seem to wander slightly. Anyone else notice this?

My wiring pinout: http://limitedslip.net/wp-content/grand ... g_id91.pdf

[akluminus]

Here is my current .msq and tables for anyone that may find them helpful. I have not finished them! I started rich and worked my way down. The 5K RPM+ fuel settings are still off, and I haven't fixed the timing table yet.

It would really help to see a tuned m30 N/A (or boosted, will just ignore 100kpa+), 93 octane ignition table. I moved a lot of the timing to be more retarded in safety. The plan is to get to a dyno, but it would be nice to bring them up some more when I get the fuel straightened out.

Target AFR:


Fuel:


Ignition:


MSQ:
http://limitedslip.net/wp-content/grand ... 9_id92.msq

[12valves]

I posted VE and spark tables for an M30B32 a while back http://www.mye28.com/viewtopic.php?f=3& ... 3#p1226673

[akluminus]

I posted VE and spark tables for an M30B32 a while back http://www.mye28.com/viewtopic.php?f=3& ... 3#p1226673

Oh, awesome! This is exactly what I was looking for, thanks!

[akluminus]

Here is another tidbit for the search engines and future megasquirt installers. My 1984 m30b32 e24 had a two wire bosch idle control valve, but apparently an older variant that used a plunger valve instead of a rotating valve. I was having trouble getting it working smoothly when I just gave up and found a rotating type two wire idle control valve. So much easier to setup. So if you have an idle valve that looks like this (note the adjustment screw), you may be better off finding a newer two wire valve: