MegaSquirt

axco

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All the threads I been reading here refer to a MegaSquirt II CPU. I contacted DIYAutotune to purchase parts required for the conversion and they recommend MicroSquirt. There input: "A MicroSquirt may still be your best bet. You can use it for three spark output channels when you put it on the six cylinder, and it's very flexible when it comes to inputs and outputs."
Apparently this is a less expensive setup to convert the E9 and according to their parts list it uses a MPS. Love to get some input here
 

sfdon

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After I read the starting instructions for micro squirt I ran far away...,,

Typically, the first time someone tries to start their engine with a MicroSquirt® controller, it starts after about 5 minutes of alternating various cranking pulse widths numbers to get started, and changing the:

Cranking Pulse Widths:
The cranking pulse width at -40°F should be about 3 to 5 times the 170°F value.
If you over-estimate the correct values, you WILL flood the engine.
To begin, set the -40°F cranking pulse width to about 88% of your 'upper' req_fuel value, and the 170°F cranking pulse width to about 23% of your req_fuel. Those should get you 'in the ball park' for starting.
Once you have the engine running, you can tune the cranking pulse widths with small changes, moving them up or down together, and check it over a few days worth of starts before deciding which direction to go next. Remember that the cranking pulse widths need to be with ~0.5 milliseconds of the optimal value at both -40ºF and 170º F.
You move them up and down together, but not by the same amount. You want to keep the cold cranking pulse width about 3 to 5 times the hot cranking pulse width.
For example, suppose your reg_fuel was 14. Then you might start with a cold cranking PW of 12.3 and a hot cranking pulse width of 4.0. Suppose you try this and see it is too rich, and your temperature when you tried it was 40°F. So you need to lean it out (after making sure the engine hadn't flooded, in which case you would have to clean the plugs). You might try reducing your cold cranking pulse width by 0.8 milliseconds, to 11.5. You don't want to also reduce you hot cranking pulse width by 0.8. You really want to reduce it by the proportional amount you reduced the cold pulse width, which would be 0.8*(4.0/12.3) = 0.26 = 0.3. So you would reduce it to 3.7.
This maintains a reasonable ratio between the pulse widths. You don't have to calculate it each time though, just adjust the hot number by about 1/3 of the cold number, and you should stay 'in the ballpark'. Conversely, if you had to richen the pulse widths, you might add 0.8, and 0.3, etc.
 

afeustel

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Don,
Are you recommending something other than the micro squirt?

Do you recommend an MSPNP2 or MSPNP3?

Doesn't the MSPNP have a micro squirt controller inside?
 

sfdon

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I'm thinking I like that part about Plug and Play.
No doubt I'm invested in MSPNP2.
There is an option- let's put Sven and Drew (arguably
two of our brighter members) together and have them
report back to the forum about the micro squirt?


Microsquirt module

The Microsquirt-module comes as a bare PCB and is most often used to form the core of a packaged ECU. For example, the DIY-PnP range from DIYAutotune use the Microsquirt module at the heart. The module is specifically intended to form part of your product with licensed B&G hardware and firmware of your choice. It is not intended for novice end-users.
 

Sven

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I have never spent any time investigating microsquirt since initially, back in 2007 when I started with MS, it was designed for motorcycles and such.

The MS2PNP is the simplest way to go since you can use most/parts of the Motronic 1.3 harness. It is especially nice if you already have a coupe with the Motronic conversion.

I have only worked with the MS3, which is their full featured setup with custom wiring harness. Room to add second MAP sensor for BARO, individual injector control, AC fan control, EGT's, multiple O2 sensors, other inputs (Evap canister, etc), wasted spark, and some I can't think of right now.
 

sfdon

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I like simple-hell I'm big on simple!

I remember reading the inter web about micro squirt and saying that's not for me.
4 years ago when you set up your MS early version you had to click on micro squirt
On the drop down menu.

Here's what I saw:

MicroSquirt your Motorbike/PWC/Snowmobile!

MicroSquirt EMS-- Full Standalone Engine Management giving you full control of your Electronic Fuel Injection and Ignition system for your Cycle, ATV, Boat, PWC, Snowmobile, and yes you can put it on a car even though it was really designed with these other applications in mind... The MicroSquirt Engine Management System is small but feature packed, and at a price that can't be beat. The regular MicroSquirt is a full EMS, while the MicroSquirt Module puts the MicroSquirt features on a circuit board for installing into other devices. You gotta check it out...
 

aearch

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needs to be tuned by shop

To run megasquirt or k-data, you will need the following:
a. 60-2 harmonic dampener
b. vr pick up for the dampener
c. wideband 02 sensor
d. GM temp air sensor
 

sfdon

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Hi Alan. Any suggestions on where to buy those things? thank you.
 

aearch

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afeustel

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There is an option- let's put Sven and Drew (arguably
two of our brighter members) together and have them
report back to the forum about the micro squirt?

Don, I appreciate the nod but honestly, the only reason I know ANYTHING about the MSPNP2 setup is because of the assistance provided by you and Sven, and shared co-miserating discussions with Wayne.

You and Sven are the masters, no doubt, and you are both commended for your willingness to help those of us who often just don't get it.

I am very pleased with the MSPNP2 setup on the Bav. The car runs great and for those considering a conversion from carbs, it was really not that terrible of a task. Not trivial, but definitely doable. That said, it helps to read as much as possible about the systems and operation prior to picking the brains of Sven and Don regarding any specifics related to BMW applications.

For the Coupe I am planning to use the same setup that I did for the Bav. I could have sworn there was an MSPNP3 but looks like I was mistaken. I think the most recent version of PNP2 has additional serial output pins and A/C idle kick up control compared to the version the Bav is running. I am running wasted spark with MSPNP2 and will do the same with the Bav (distributor delete).

Probably one of the biggest challenges is getting the wiring harness right. I built mine from an existing 92 7 series harness and gutted it for all unused wires, then added additional needed for wasted spark and some ground lines and wrapped it all back up. Helps to do it this way so that you can integrate the firewall wire harness grommet so that it does not have to be split/slit. It does not matter if you use an automatic or manual harness as a base, but you need to be sure about the pin mapping on the 55-pin bosch harness.

For 02 controller I used an NGK Powerdex system (~$300), but it looks like there are less expensive options out there now. Crank position sensor was from Autoparts warehouse for about $30. ICV was also purchased from Autoparts warehouse for about $86.

Happy to help with any questions but know that you are getting second tier advice.

Drew
 

charofire

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Axco - you are correct. The DIY BMW Plug n Play kit uses a MicroSquirt module. Taken directly from the DIY webpage- http://www.diyautotune.com/catalog/megasquirtpnp-g2-b8793-for-the-8792-bmw-e30-325i-p-502.html:

New second generation MSPNP!

We've totally redesigned the MSPNP! This new second generation unit runs MS2/Extra code, using the MicroSquirt Module and a lot of new MSPNP-specific hardware. We've added several major improvements over the original. Here's the features of the new model.


There are kits you can buy from DIY that are not assembled, and will lack some of the hardware advantages found in their Plug n Play units. Even the brightest can mess it up with all the required soldering and wiring. Ask me how I know. I bought one from an experienced installer several years ago and my car ended up stranded in Palm Springs for a few months. Once it was sorted, I had a great tune for about 3+ years until switching injectors. There is security going with a Plug n Play kit that cannot be denied. For instance, the DIY BMW PNP kit allows one to use low impedance injectors without any additional wiring. Most of us will not use low impedance injectors though.
 

sfdon

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Do not for any reason use low impedance injectors with MSPNP2.
I have a letter from Matt explaining the problem.
Just don't go there.
 
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