JustinL

I'll preface this by saying that I haven't tested all conditions with the microsquirt and as I type this I've got about 5 minutes of long term testing. For anyone who doesn't know what microsquirt is, it's a miniaturized version of the opensource Megasquirt II unit. It's advantages for our application are the dual VR inputs and low cost. More information can be found at www.microsquirt.info

Going to stand alone engine management will give you the ability to tune ignition timing and fueling. You can also ditch the air flow meter and really free up the intake. I expect power gains but that will be based on the skill of the person doing the tuning.

What you will need:
1 944
1 Microsquirt $400
2 Ballast resistors (7.5 ohm, 25 watt aluminum housed) $20
1 GM MAP sensor (I used 3bar and in retrospect should have gone smaller) $64
1 Intake Air Temp sensor $17
1 Laptop with a DB9 connector
1 Basemap (Free!)
Assorted electrical tools, heatshrink tubing, etc.




What I recommend:
Wideband O2 sensor (highly recommended)
Timing light
Scrap DME


I have used a spare DME box provided by a friendly pelicanite to use as a swappable ECU. I can switch back in my motronic just by switching the dme wiring harness back over.

This is how the box looks with the cover off:

The wires you need to connect are as follows:

Power:
DME pins 18 and 35 to AMPseal Pin 1 (red wire)

Grounds:
DME pins 16,17,19 to AMPseal 21,22,23 (Black wires)

VR sensor-
DMe pins 25,8 to AMPseal pin 33 (silver coax shield)

VR input 1+ (speed sensor)
DME pin 27 to AMPseal Pin 32 (silver coax center (White wire))

VR input 2+ (reference sensor)
DME pin 26 to AMPseal pin 4 (brown/white stripe)

VR Sensor shields:
DME pins 5,23 to DME pin 28 (ground)

Fuel Pump:
DME pin 20 to AMPseal pin 8 (purple)

Injectors:
DME pins 14,15 to Ballast resistor to AMPseal Pins 9,10 (blue and green)

Ignition:
DME Pin 1 to AMPseal Pins 11 AND 12 (White/red, White)

Coolant Temp:
DME pin 13 to AMPseal Pin 25 (Yellow)

Intake air temp and MAP sensor wire according to microsquirt.info instructions. Use 5v vref and sensor ground from AMPseal.

O2 sensor
AMPseal pin 34 to either external WBO2 or to DME pin 24

Tach (I don't have this working yet)
DME pin 21 to AMPseal Pin 35

Optional wiring

Air Flow Meter (for map/maf blending)
DME Pin 9 to AMPseal Pin 29

Idle valve (I don't have this figured out yet, but it idles fine without it)
DME pin 33 or 34 to AMPseal pin 7 (green)

Boot loader
AMPseal Pin 15 (purple) to grounding switch

Throttle position sensor (you can run without this on the n/a so this is turbo wiring)
KLR pin 21 to AMPseal pin 28 (5v vref gray wire)
KLR pin 22 to AMPseal pin 27 (sensor wire)


If you do it like me, it will look like this when wired in:




You will need to upload a basemap and here is the current version that I have (right click save as): http://www.ualberta.ca/~jlewicke/porsche944running.msq

I just went out for a drive with this map and it bucks and coughs with much load, so my ignition table needs work. Free revving, it revs up quite nicely to around 3500 RPM.

Of course this is an install at your own risk and I don't guarantee this will work for every setup. Proceed with caution and check things as you go. Read lots about megasquirt and microsquirt. I am happy to help people with problems they may have and answer questions, so ask away!

The project thread is located here to see the trials and tribulations I had along the way. http://forums.pelicanparts.com/showthread.php?t=365785

JustinL

Fishey

Very nice thread way to go man

DanG

FYI, e30 BMWs use the exact same connector for their DMEs (probably a very similar bosch EFI system). Its really easy to find e30 DMEs for free or close to it.

Great work Justin! I'm glad to see the uS/MSII is capable of handling the stock VR sensor inputs. That's gonna make the system much more popular with this crowd.

alex

This needs to be at the top this morning.

marky522

I have been following this on Pelican for a while, I cant wait to try it.

Mark

alex

I read through that whole thread last night. Very cool.

JustinL

I'm hunting for a power cord for my old laptop now so I can try running it without the USB-DB9 converter that was causing all the resets. I know my ignition table needs serious tuning. I'll try to keep up with the updates as I go. If someone wants to download the .msq and make suggestions to the table, I'd like to hear it.

RobHeinl

Thowing a very interesting idea out there for thought-
Bruce Bowling (co-originator of MS) stated in his 2008 State of the Union Address:

"Also, there appears to be a demand for the idea of a MicroSquirt plug-in daughterboards which would consist of the MicroSquirt SMD board assembly minus the connector, case, and harness. Sounds good -- let's do it! The plan would be to replace the ampseal footprint on the board with 2x18 header row (0.1 inch). Now the MicroSquirt becomes a complete plug-in ECU that is fully tested and ready to be used for any DIY-designed mainboard. People wanting to design replacement ECUs for older vehicles could take the MicroSquirt module and design the interface and I/O board and have a ready-to-go setup. Since almost half the cost of MicroSquirt is the enclosure, case, and harness, I suspect the MicroSquirt module would be in the low US$200.00 - probably the most price-competitive arrangement and most reliable available for experimenters. And the smallest - a complete engine controller the size of a business card! "

This would allow us to drop the Microsquirt into the old DME and straight-wire the DME connector and keep it all contained within the original casing. No need for another harness or a different casing... and it's cheaper (~$200)!!!

Campeck

AHA! so Thats probably my problem with the smt-6...
awesome thread. Im sure there are alot of people who will use it as a guide. maybe even me!

Rogue_Ant

Got a link?


-Rogue

pete95zhn

I have been playing with VEMS ( http://www.vems.hu/ ) installation to 951. It also utilizes stock VR-sensors. While it's probably the world's first ( or at least among three first ) one with 132+1 triggering, it has had some teething problems. Because I'm somehow retricted in programming ( yeah, I know...shouldn't have gone into this etc ), I've been dependant of help of other VEMS users, mainly Audi-crowd with 135+1 triggering.
When triggering problems were finally solved another big one come out, causing a lot of disbelief. This was found out ( a week ago ) to be caused by conflicting firmwares. For Auditrigger an experimental firmware ( 1.1.24 ) was developed, but latest firmware I had intially downloaded ( and which still is published as non-experimental ) was 1.1.23, including the MegaTune. Unfortunately I was unaware the fact ( Yes, Wiki sucks! ) that I should have changed .ini -file from 1.1.24 to 1.1.23 to get MegaTune work properly. It also caused illogical behaviour of fuel injection. One symptom was inability to lean the mixture under load, causing the car to " hit the wall " when flooring...with thick, black smoke...
When this finally was corrected, my car started running properly. Warm-up -enrichments are set, original ICV works and idle is smooth at 850 rpm. It revs freely and builds boost on the road, even the VE-map is quite correct, AutoTune and VE-learning are very helpful!
The drawback with fuelling problems was engine break-in with overly rich mixture, which caused piston ring glazing...so I'm now pulling the engine apart...

My Wiki homepage: http://www.vems.hu/wiki/index.php?pa...age%2FPeteKrgr

My VEMS installation in short:
-original VR-sensors
-modified original harness
-low-Z injectors with ballasts
-Wasted Spark programmable ignition
-sequential injection
-MAP, IAT & CLT -sensors
-16x14 maps for VE, spark and lambda
-autotune
-active knock control
-possibility for anti-lag, launch control, and boost control



Sorry about his slight hijack! Good luck for your project, keep us updated!

PS. I was not able to establish a connection between my laptop and the box with UBS to D-sub adapter, there were weird behaviour of functions and multiple resets. It was cured when I bought a PCMCIA to D-sub adapter.

DanG

http://www.msefi.com/viewtopic.php?f=92&t=31305

bad_monkey

This is the way I'll be going with my 2.7 car, I just need to find some base maps, or maybe translate them from somewhere (FRWilk?) - I wonder if the 2.5l basemap would work? Perhaps I should just add a small percentage of fuel to the base..

RobHeinl

You could increase the Required Fuel from 15.5 to, say, 16.5 or so. There is a nice autotune feature so tweaking the fuel map is really not a difficult task, that is if you're gonna get a WB 02.

JustinL

What we really need now is a good N/A ignition timing map that has manifold pressure vs. RPM.