Microsquirt (less expensive/super compact/less feature version of megasquirt)

[tryingbe]

I was experiencing electrical issue with my car and decided it isn't worth my time to troubleshoot the 32 year old computers or wiring. Wanting to keep the car, aftermarket ECU is the only option and Megasquirt / Microsqurit sounded good.

Wanting to keep everything simple, I went with batch firing injectors and waste spark ignition system, so the compact\slightly cheaper Microsquirt would work fine for me. I will only need one crank sensor and a 36-1 wheel welded to my crank since factory turbo HEP is not supported and I never like that HEP sensor anyways.

For reference.

The LM used a Motorola 6803U4 processor operating at 1 MHz, with 256 bytes of RAM and either two 8K EPROMs or one 16K EPROM.
From 1988–1989, a SMEC (Single Module Engine Controller) was used. This was a complete redesign of the older system, using modern CAD for board design, and higher density SMD components. The processor was a 68HC11 operating at 2 MHz with 256 bytes of RAM and a 32K EPROM. Functionally, the SMEC was the combination of the earlier Logic and Power modules into one unit. Starting in 1990, a more advanced SBEC (Single Board Engine Controller) was used, which integrated the earlier two board computer into a single board.

https://en.wikipedia.org/wiki/Chrysl...%26_2.5_engine

MicroSquirt uses 16-bit MC9S12C64 at 24 MHz, ROM is 128 kB, and RAM is 4 kB
https://en.wikipedia.org/wiki/MegaSquirt



My Microssquirt input/outputs are the following.

Inputs are:
crank/hall sensor, shielded from the shielding of a coax cable. Thank you A. J. for the tip. (no need for cam sensor)
coolant temperature sensor (Chrysler sensor)
air temperature sensor (open element Chrysler sensor)
throttle position sensor (Stock Chrysler sensor)
ethanol sensor (GM sensor)
o2 sensor (AEM Uego with 5v output)
manifold absolute pressure sensor (GM 3 bar map)
knock sensor - All MS needs a knock sensor controller. I use lilknockmeter by http://www.insaneimportperformance.com/ which can display light, has headphone output, has on/off digital output, as well as analogue output... :yeah!: Dodge 2.2/2.5 are very noise engines. Stock ECU consider .8V is a knock at 2000rpm, while it consider 4V is a knock at 4000RPM. So I need something that can give me an analogue output.
A/C sense wire - wired to the a/c control so microsquirt can raise idle speed if a/c is on.

Outputs are:
idle control, ford PWN idle valve. Edit: Upgraded to Volvo BOSCH valve.
tachometer
two set of Ignition coil (goes to 420a coil)
two set of injectors (75lbs low impedance injectors with a Volvo injector resistor)
a/c cut off relay wire
fan relay wire - works great.
fuel pump relay wire

Boost control is handle by my HDi electronic boost controller, and I am very happy with that.
Added an external voltage regulator, super easy to do.


Megasquirt has more options I'm sure, but I don't need them, why pay for them?

I have almost $1500 into parts plus shipping

Microsquirt + 8 ft harness $369
36-1 wheel $32.00
Weld 36-1 wheel to crank $100
crank sensor $43
QuadSpark $89.00
MAP sensor connector $8.50
MAT sensor connector $10.00
ECT sensor connector $10.00
TPS sensor connector $10.00
420A wires $20
420A coil $20
Wiring Connector packs $30
USB to serial $15
Misc wires $40
Uninsulated crimp $20
Crimp tool $13
Shrink Wrap $10
Misc bolts $15
Relay $15
Fusebox $25
Fuses $5
E85 sensor + connector $80
lilknockmeter $120
Bosch knock sensor + wire connector and stud. $40
Injector resister $30
wire loop $20
On/off Solenoid valve for idle control $30 (upgraded to a FORD PWM idle valve for wider RPM control). Edit: upgraded to Volvo BOSCH valve for more air flow for my a/c control.
3m tape $6
Tuner Studio + Megaviewer $80
etc...

Separating engine harness with body harness.



Test Mounted.


All needed wires labeled.


Made bracket for crank sensor.


Welded and ready to be worked on.


Painted the crank and reinforced bracket.


Mounted my 420a coil on my distributor, after taking all the moving parts out of the distributor. The distributor mounted like that is due to lack of space. I'd like to change my oil filter without taking the coil out.

Some people have coil on plug, I have coil on distributor


After some long hours, the car started on Microsquirt yesterday.
Top right corner is my ethanol sensor.


I still have a lot to do but just hearing it start again was so nice. Now is clean up and tuning time.

http://minimopar.net/ and factory repair manual will be your best friends. Thank you Russ W. Knize for minimopar!

Micrsosquirt Manual http://www.msextra.com/doc/pdf/html/...dware-3.4.html

[wheming]

Cool news!
Glad it is back running.
I must say, i have thought about this too for when we can no longer justify keeping old wiring working.

[contraption22]

Welcome to MegaSquirt!

[tryingbe]

I must say, i have thought about this too for when we can no longer justify keeping old wiring working.

My hazard has never worked since I bought the car over 10 years ago. While I was adding fuse boxes for Microsquirt, I figured out why. The wire is corroded at least 10 inch inside the insulation after the fusible link.





Now my hazard light works perfectly.

[zin]

Seems like the way to go to me. I'm not super confident in the old harness wires, etc, when they could cause major destruction on a "hopped-up" engine if say an injector driver gets wonky...

Curious as to the tune, is there an easy way to import the spark/fuel tables from one of the existing cals (mopar perf or turbonator)? Having to re-invent the wheel in for the new ECU would be a pain...

Mike

[thedon809]

I don't know if I could justify a 1k when I can burn chips and datalog for $150 but it would be nice to have some modern tech. I'm assuming you marked the crank pulley so you don't put it on wrong if you ever have to remove it?

[tryingbe]

I don't know if I could justify a 1k when I can burn chips and datalog for $150 but it would be nice to have some modern tech. I'm assuming you marked the crank pulley so you don't put it on wrong if you ever have to remove it?

I burnt those chips and used ostrich, made 290WHP with it too. But let me ask you this, when the 32 year old wiring and computers give out and you want to keep the car, what would you do? Put another 30 year old wiring in there? For me, it's either put money in or part it out.

If you open the picture of the painted crank pulley, you'll see a triangle pointing at the crank sensor.

[lightbulb010]

What's the part number/application for your IAT sensor?

What do you think about the knocksense? I've been thinking about adding that to mine but I don't know if I could put my trust in it. Does it work well enough to rely on or is it more of a worst case scenario warning?

[tryingbe]

What's the part number/application for your IAT sensor?

What do you think about the knocksense? I've been thinking about adding that to mine but I don't know if I could put my trust in it. Does it work well enough to rely on or is it more of a worst case scenario warning?

I don't remember. You can go get one here. https://www.diyautotune.com/product/...-with-pigtail/

I'm still at only idling the car, can't take it anywhere yet.

Why can't you put your trust in knocksense? You trust your factory knock system, don't you? Knocksense can send signal to the MS as well as flash a LED to let you know knock detected, sounds like a win to me.

[thedon809]

I burnt those chips and used ostrich, made 290WHP with it too. But let me ask you this, when the 32 year old wiring and computers give out and you want to keep the car, what would you do? Put another 30 year old wiring in there? For me, it's either put money in or part it out.

If you open the picture of the painted crank pulley, you'll see a triangle pointing at the crank sensor.

Rebuild it most likely. At least when I swapped my Omni to smec I went through every inch of the new harness. It's not too hard to pull the entire harness on these cars. Not like some of the newer cars I've worked on. If I did something like this it would be more for the newer faster computer than the wiring. Oh ok, so if you put the car at #1 TDC the arrow would be pointing at the crank sensor?

[tryingbe]

Rebuild it most likely. At least when I swapped my Omni to smec I went through every inch of the new harness. It's not too hard to pull the entire harness on these cars. Not like some of the newer cars I've worked on. If I did something like this it would be more for the newer faster computer than the wiring.

I remember spending days to figure out why the alternator wouldn't charge. It turned out to be a pin not making good contact inside the LM plug to the LM, that was the first week of owning the car. Reverse lights not working? Light bulb connector corroded. Hazard lights not working? 12v feed AFTER fusible links corroded, no tear or rip, just corroded. Turning A/C on and made the car goes to 12 A/F at idle, nope tuning it out will make normal idle rich. Car runs perfect one second, and next second it needs a re-scale of injectors to make everything 17% richer? Yeah, thanks, but no thanks, not troubling shooting that. Time for me to move on and leave the 30 year old wiring and computers out.

Oh ok, so if you put the car at #1 TDC the arrow would be pointing at the crank sensor?

You got it.

[contraption22]

Seems like the way to go to me. I'm not super confident in the old harness wires, etc, when they could cause major destruction on a "hopped-up" engine if say an injector driver gets wonky...

Curious as to the tune, is there an easy way to import the spark/fuel tables from one of the existing cals (mopar perf or turbonator)? Having to re-invent the wheel in for the new ECU would be a pain...

Mike

I dunno about tuning the OE tables, but if you can put those tables in excel, you can dump them into Tunerstudio (the tuning software for MegaSquirt)

[Aries_Turbo]

I dunno about tuning the OE tables, but if you can put those tables in excel, you can dump them into Tunerstudio (the tuning software for MegaSquirt)

timing you most definitely can.

fuel.... fuel is a little stickier. you could calculate a map of pulsewidths from a solidly tuned cal to get the shape of the VE map. then measure what VE value gets you a given pulsewidth in a low RPM WOT (less dangerous) part of the MS map and convert the pulsewidth map to VE values as a base tune maybe.

fuel is pretty easy on MS though with the autotune part of tunerstudio.

Brian

[Aries_Turbo]

i so want to put a microsquirt on my suzuki GS1100E.

Brian

[johnl]

Harry - you're way better than me. Cool beans.

[wheming]

i so want to put a microsquirt on my suzuki GS1100E.

Brian

You have got kids, AND you get to keep your bike?
Geez.

[Aries_Turbo]

You have got kids, AND you get to keep your bike?
Geez.

"You realize that you are arguing against bikes with a dude that grew up on the back of his mom's and dads bikes?" Brian Bucar said to his wife.....

I'm super careful and wear lots of gear. :-)

[lightbulb010]

I don't remember. You can go get one here. https://www.diyautotune.com/product/...-with-pigtail/

I'm still at only idling the car, can't take it anywhere yet.

Why can't you put your trust in knocksense? You trust your factory knock system, don't you? Knocksense can send signal to the MS as well as flash a LED to let you know knock detected, sounds like a win to me.

It's not that I couldn't put my trust in it, but I wouldn't unless I knew how well it actually works. By that I mean whether or not it's able to be sensitive to slight knock without being falsely triggered by other engine noises. I know a lot of people have used it but there are a lot of factors that come into play for a knock detection system. For example a 2.2l in a cavalier(push-rods) may or may not be able to have as sensitive of a knock detection system as a Chrysler 2.2l could just due to the extra noise I would imagine is transmitted into the block through the valvetrain. Also, Just because they are both 2.2l engines doesn't necessarily mean that the audio frequency that knocking will produce will be the same due to the block being vastly different.

I'm not, by any means, trying to say that knocksense is a bad product or that it's not effective. I just don't have any experience with it or any similar systems and I was wondering what your thoughts are.

You're going to love megasquirt by the way. I love being able to make changes on the fly and the flexibility of the system. Tuning closed-loop idle is a little tedious but once you have it dialed in it never fails.

[contraption22]

You're going to love megasquirt by the way. I love being able to make changes on the fly and the flexibility of the system. Tuning closed-loop idle is a little tedious but once you have it dialed in it never fails.

I'm not running air conditioning, so it's easier for me, but I have gotten my idle pretty stable just by adjusting timing and fuel. My IAC is blocked off.

[Force Fed Mopar]

Just an FYI, the factory HEP will work with Megasquirt. I know a guy running it on his carbed car.