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Microsquirt 1985 Dodge Omni GLH Turbo

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I have a 1985 Dodge Omni GLH with lots and lots of modifications, staying 2.2L block and 8 valve cylinder head. It made 290WHP at 20psi on E85 couple years ago on a socketed 1987 Dodge logic module ECU that I programmed. I was experiencing electrical issue with my car and decided it isn't worth my time to troubleshoot the issue, since there is only two possibilities, computers or wiring, none is available new. Wanting to keep the car, aftermarket ECU is the only option and Megasquirt / Microsqurit sounded so good.

For simplicity sake I went with batch firing injectors and wasted spark ignition system, so the compact\slightly cheaper Microsquirt would work fine for me as I will only need one crank sensor and a 36-1 wheel welded to my crank. Factory Chrysler's 2.2/2.5 hall effect sensor/distributor setup is broken on MS.

My Microsquirt input/outputs are the following.

Inputs are:
crank/hall sensor, shielded from the shielding of a coax cable.(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 (knocksense controller
A/C sense wire

Outputs are:
idle control (on/off solenoid, not the stock stepper motor)
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
fan relay wire
fuel pump

Boost control is handle by my HDi electronic boost controller, and I am very happy with that.
Added an external voltage regulator from a 80's dodge truck for the alterantor, super easy to do.
Changed all factory fusible links to PAL fuseblock, and added a blade fuseblock for Microsquirt with an relay for ignition switch on

I have roughly $1225 into Microsquirt related parts

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
knocksense $80
Injector resister $30
wire loop $20
MAC valve for idle control $30
3m tape $6
Tuner Studio + MegaViewer $79.95

Separating engine harness with body harness.

Welded the 36-1 wheel to my crank pulley

Microsquirt and Quadspark at stock ECU location

Some people have coil on plug, I have coil on distributor!
Mounted my 420a coil on my distributor, after taking all the moving parts out of the distributor.

Welded some 1/4" thick metal for my crank sensor bracket.

Injector resistor, on/off idle solenoid, and 3 bar map under the solenoid

E85 sensor

Boost control solenoid, hobbs pressure switch, (opens at 0psi to control the solenoid that allow blowby to from Valvecover to pre-turbo piping), PCV blowby solenoid

Fuseblocks, PC680 battery, and Volvo radiator fan relay

Wiring mostly cleaned up

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Can you explain the solenoid for crankcase gasses a bit? 

Think you'll pick up any power with the swap to microsquirt?

Was the stock EMS sequential injection? If so, how much of a degradation in idle quality did you notice?

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Turbo Dodge had batch firing system until after 1990. My car is a 1985, so batch firing is stock. I've gone from stock 34lbs injectors to 75lbs injectors and I never had idle quality issue, not even with stock computer with a chip that I programmed myself. People has idle/rich issue usually buy aftermarket off the shelf tune instead of tuning the engine themselves. I tuned my buddy's Dodge 2.4L turbo engine with 120lbs injectors, no idle issue there either.

My PCV system is simple, in vacuum, crankcase gas goes to my intake via PCV catch can. In boost, the crankcase gas goes to pre-turbo piping. Pistons rings on turbo Dodge is pretty loose, this way, it keeps the oil smoking to minimal. I would love to have a vacuum pump with a large enough volume but this will do for now.

I just did emission and the car runs cleaner than it ever did on stock computer. I will definitely pick up more MPG as I can set cruising at 16:1 vs stock 13.7-14.1:1 ratio. I noticed when I set ignition timing with stock computer and distributor at idle speed, timing always jumps from between 10 BDC to 14BDC, it would NEVER settle at just 12 BDC like the factory manual calls for. With Microsquirt and a 36-1 wheel, ignition timing is bang on EVERY time. Also, there is the issue that stock computer doesn't have enough time to do precise calculation above 5454 RPM due to the stock ECU is a 6803U4 processor at 1mhz and has a loop time of 22ms. So, at above 5454 RPM, the stock ECU would skip the calculations and uses previous value for timing and fuel. Microsquirt has a  MC9S12C64 at 24 MHz  and a loop time around ~.33ms.

Since my engine likes to make power up top, I wouldn't doubt the engine can take advantage of precise ignition timing and ECU calculation power. Will have to dyno it once all the tuning is done.



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