Evinrude MegaSquirt Injection ECU

[PanRonnie]

Water cooled would be the best for marine use, make back plates with passages to draw off the heat. All my stuff is on the ph and no issues so far.. The efi technology cdi suff is amazingly small and seems to handle the job they have internal temp sensors you can use for logging or indication. Found the ones I have used new prices are crazy but their stuff is top shelf. There are 2 boxes one above each head.

That looks fantastic but i think that is out of the price range of most dabbelers
When i build the DC-cdi units i was thinking there must be an easier and most of all cheaper way
So i build with the help of a diy motorcycle cdi specialist these switch boxes as i could not get the mercury boxes to spark with a logic level output
There might be a chance you can trigger the omc powerpack as it would have the 6 seperate inputs but these boxes should also fit
Now as far as i know only megasquirt can drive them as you can set the coil dwell to a fixed percentage of crank rotation
As the thyristor opens on a positive going of the input and most units see this as the start of the coil dwell not the ignition point this is a problem
The way i worked around this is a coil dwell of 95% going low
So the thyristor input was low 95% of the crank rotation giving the capacitor time to charge
When it's time fir ignition the logic level goes high firing the thyristor and giving spark
Megasquirt sees this as the ignition point
With the normal coil signal it goes high when it starts with the coil dwell and goes low when it is time to spark so this would give the wrong timing and as rpm increases your ignition point would advance as your rotation time gets shorter and your coild dwell becomes a higher percentage of the rotation time

[BLisBack!]

Interesting. Triggering a CDI with a circuit intended for inductive style ignition. That'll work I guess. The SCR/Thyristors only need a whiff of that long pulse as you stated and they are full on.

What are you using as the coil primary power source? The OEM charge coils under the flywheel?

I believe the OMC power packs use a Triac and are triggered with a negative pulse from the trigger base (sine wave analog output). Lawn mower grade stuff but they were just trying to keep it simple so you can't bust 'em too much. Might be why you couldn't get the Merc box to trigger, probably very similar.

-BL

[PanRonnie]

Yep you just hook up the original wiring don,t even have to change the wire terminals
This the omc patent circuit diagram with the warm up thyristeros inplace
You could essentially sperate this circuit by disconneting the powercoil to the powerpack obviously leave the 12 volt wire from the starter solenoid
you would loose the warmup but also the REV limit from the LM2907 as no frequency is coming in

[PanRonnie]

I also build a second version with even less parts you could run the evinrude v8 with 2 of these boxes
Included the full omc ignition patent here

[PanRonnie]

If you want to build the circuit yourself
The single capacitor is simply one bridge rectifier with the 4 thyristor circuits

[PanRonnie]

the mercury 2.5 shematic

[H2OPERF]

Yeeaaa.. that stuffs wayyy past my pay grade lol...

[PanRonnie]

Actually still have some videos with it
https://youtube.com/shorts/46q35k1UNMM?feature=share

And out on the water only tuned to 5000rpm did not dare to use autotune above that

[PanRonnie]

https://youtube.com/shorts/xEMg9QprdBM?feature=share

[BLisBack!]

I like the vid on the water! Aluminum melts at 1200, you got plenty more to go!

-BL

[powerabout]

anyone tried a zeeltronics package?

[PanRonnie]

I like the vid on the water! Aluminum melts at 1200, you got plenty more to go!

-BL

Well that is one of the interesting things
When i started actually with the Uk based system DTA the dealer asked me to make an EGT curve from my engine
Now this was my 98 promax 225 which after suffering 2 piston failures got the new A32 ecu, part of the bulletin is reducing the igntion to 23 dgr BTDC mine was somehow set by the mercury dealer to 17 dgr BTDC figured this out only later
So the EGT curve which i included is from a stock 225 with an 17 dgr BTDC setting
That was also a thing when i was out on the water i got it to run good but what was the limit?, the engine was ported in the meantime "never a good thing to change more than 1 thing at a time"
When i got the change to buy a skater 24 i rebuild everything back to stock with the mercury computer and use megasquirt only for datalogging
first getting some proper EGT and AFR,s of 2 engines even the cooling system already gives different EGT temps one is poppet the other flow

That is one thing i would advice everybody first install the unit as a datalogger get some good readings from your topcondition outboard make yourself familiar with whatever software then start introducing it to the engine either ignition or fuel but not both at the same time
this way you have something to tune against your datalog
Oh yeah and do proper injector dead time tests with your ecu

[BLisBack!]

... part of the bulletin is reducing the igntion to 23 dgr BTDC mine was somehow set by the mercury dealer to 17 dgr BTDC figured this out only later

You mean it was inadvertently set to 23 and you reduced to 17?

Yeah good advice to get a baseline first on a known working motor. With VSFI on a fresh motor, I start with a known working map, do an overall increase on all cells of about 1 to 1.5ms (Alpha-N mode). This puts EGTs in the 800-900 range (very safe) but allows the motor to still get up to speed. Then use the hand-held to tune in the map dynamically on the water. Usually doesn't take long at all and you're screaming along with EGTs 1000-1100. In Hand-held Tune mode the changes go directly to the map not used as a Trim on existing map values. (you can set it to do either)

Same with ignition timing, back down about 2-3 deg from the OEM recommended settings and work up. Then put in a WOT retard as much as possible to where it isn't a noticeable power loss.

-BL

[PanRonnie]

You mean it was inadvertently set to 23 and you reduced to 17?



-BL

other way around