[Magnum828]

So hello, I'm 17yo student from Poland. I would love to convert my little rocket from carburetor to EFI.
So I would like to control ignition and fuel from speeduino. I will use J121 igniter with stock coil and for injection I will use throttle body from 900cc Seicento.
BUT there is one "small" problem, the decoder wheel.
It has three teeth, unevenly spaced.

Number one tooth means TDC. The wheel is turning clockwise. It is an two cylinder engine but both pistons are moving up and down simultaneously. Would love to see an implementation of this decoder. Because installing a missing tooth wheel is pretty complicated in this engine.

[theonewithin]

Even if it was supported it wouldn't provide very accurate Timi g due to only have 3 references of crank angle per rotation.

Does it have a distributor? Can you fit a wheel and sensor on it instead?

If not then I would highly recommend replacing trigger wheel.

[Magnum828]

But the stock ignition module works with three points of crank angle position. My Fiat is a later model without distributor. I was looking through the code of speeduino, and there is an implementation of getting the crankwheel speed between two points. But it is not enabled for decoders yet. Also @noisymime in other topic was talking that it would be possible to implement this.

[panpan]

Looking at the original crankshaft pulley, can you not put the pulley in a lathe and add a toothed wheel? The sensor has two fixings, maybe you could space/relocate the original sensor too? The other option is to add a wheel , like a washer to the fixing centre, so remove pulley nut, fit wheel, and re-fix nut etc, as it looks like you have a clearance issue with the drawing on the right hand side. maybe you can get an earlier or another pulley to play with?

[126p]

Hi,
This problem was already discussed here: viewtopic.php?t=80&start=60
I would also like to see this decoder. I even tried to wrote it myself but finally I used coil as a reference signal.
If you want more info about my setup, check: viewtopic.php?f=19&t=2396

[Magnum828]

@126p I have seen your setup I have read all posts about this decoder. Noisymime states it is possible to do it. Also there is a one small problem with installing wheel with other teeth. There is a centrifugal oil filter in the pulley.

[panpan]

Yes, the centrifugal filter is like the 850 Coupe, but looking at this picture, you can remove the "teeth", machine the surface flat in a lathe, and add a laser cut timing wheel to this, and use the small holes to fix this to the pulley.



Then you can use the existing sensor too.
Good luck
Mike
Edit... I'll draw it if you cannot understand, but I need to know the small hole PCD (fixing holes for centrifugal filter cover I think), and overall diameter of the pulley.

[Magnum828]

@panpan
Yeah, I will probably do it your way Thanks for an idea!

[126p]

Or buy a wheel from older model (without those 3 teethes) and screw a motorbike sprocket to it.

[LAV1000]

Or buy a wheel from older model (without those 3 teethes) and screw a motorbike sprocket to it.

+1