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By stum
Hi All,

Just back from the shed, and a hour plus playing.

I was playing with the Duel wheel, 12/2 setup. G1 and G2 connected together.

Had the timing light out and Yes my original thoughts where confirmed. Timing is moving around between starts. by about 30 deg. 360/12 = 30 so getting out of sync by a crank tooth just a thought.

We would have started the truck 40-50 times.

My original settings where
Duel wheel
12 - crank speed
2 cam speed
0 trigger angle
crank - Leading
Cam - leading
Filter off
sync No

When the engine was in the car it rand 95% good at that, When set to fixed 10 deg, timing light was at 10 deg.

When I started to play, timing was way out. set it back to 10 deg fixed. had to set the trigger angle at -28 deg to get it back. but jumped over the place on different starts.

Played with the cam trigger to falling. after I looked at my spare dizzy, as the shape of the cam wheel. but looking at the dizzy again and goggling the rotation. Leading is correct. will give the best clean transition. Will test this again tomorrow.

Also tried Sync every = Yes
Filter = Med

These helped and Speedie sometimes started rough, but came right. timing reflected this out by chunk, then back to 10. .

All look good for 10 starts, 10 deg on the money every time.

Then a few starts +ve a chunk, then a few -ve a chunk...... all over the place for some. Sometimes -ve a chunk...+ve a chunk....then back to good. these chunks looked like 30is deg, but with no markes that far out would be a guess

So tomorrow I will try, cam trigger leading. And give it 20 starts to see what happens.

Latter in the week I will modify my spare dizzy to be a 24-1 cam wheel. Has to be better. (Yea....Nar) as it will get rid off the two wheels and the sync between them.

Hope this is some use.

I will down load the Arduino IDE now and re compile the latest firmware for tomorrow


By stum
So here is my 24 tooth cam wheel. I've marked on two big black lines where the cam sync pulse would pass G1 and G2.

the smaller black line's should be the firing points for the other cylinders. so from what I have read else where pick a point between two black lines and remove a tooth.


I will do this after some more testing as above.

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20180122_214308.jpg (2.36 MiB) Viewed 2760 times
By stum

The story continues. I continued to battle with the 12/1 and 12/2 configs. trying resisters to pull the un used G1/2 to earth.... upgraded to the lattest firmware, and even tryed a bit of custom code by nosiymime. All to no availe.

The best I got it to run was as it would come out of the box. just set it to 12 (crank) 1 cam, dule wheel. 0 deg offset. and in the car it ran. once I got the dwell settings sorted would rev to red line 7000RPM. timing was accurate, with in a deg or 2. and in the car would run good 90%. witha curve ball start every now and then.

When I took the engine out and put it in the race truck things changed, got to the point where I would only get a good start 1/2 the time or less. chased my tail for 2-3 weeks. When it started good. it was sweet, but at times would start 30deg out. not so nice. Tried leading and trailing triggers, different resistors to earth on the unused......

In the end I modified my spare dizzy, removed a tooth. set it up as 24-1 cam speed. and swapped that in.
Starts every time with correct timing.
Has a bit more scatter in ign timing, about 5 deg
Once I earthed the unused G1&G2 pickups and set the unused VR input to Hall. runs smooth. (before had a miss and chuff)
But have an issue where it wont rev past 6000rpm. I think it has to do with IGN timing or Rotor position. I will get my son to help me. bit hard to start, rev and hold the timing light.
As you can see. nice clean signals.

I will update when I sort the RPM issue. Cheers
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missing_tooth.jpg (3.07 MiB) Viewed 2710 times
By choyr
Nice. Same issue with me. Having difficulty regarding the g1 or g2. Do you have ignition logs using the g signals?
What degree offset u used when you removed that tooth from the pic?
By stum
Hi Choyr,

Sorry no logs. I managed to capture the 24 tooth and it was sweet, but I could never capture both the 24 tooth and the G1/G2 trigger. as that is the bit I was missing. and did my head in. and with no scope I was lost. you can follow my journey on the twin wheel discussion. may even be a pic of the 24 tooth log there.

It was about -186(sh) basically the cut out was -90 deg from the big mark (ie where TDC (G1 or G2) would trigger. On duel wheel offset was 0 deg.

90 deg x 2 (at cam speed) = 180. was good enough to start and then with the timing light fine tune. This is on a V6 so put the missing tooth in a spot where nothing was happening. on a 4 cylinder I would have put it at 45 deg.

Hope this is of some use. Now to find my missing 1000rpm, and I will be a happy man.


but still needs some more work to get it running as well as the duel wheel (on a good start)
User avatar
Choyr - 2 answers depending on your setup for Trigger Angle: If using Dual Wheel and deleting one of the G sensors, it is critical to set the correct Trigger Offset in order to have any chance of maintaining sync. IIRC, the stock 7M-GTE for example was something like 20° after TDC of the nearest cylinder when at factory index (yours could very well be different); :!: but please do your own research or testing as that's from memory, and has more problems as listed below.

For Missing Tooth (Cam), the offset value is also entirely dependent on several factors unique to your setup, including which tooth is removed, where the distributor shaft is indexed on installation (relative to the crank position), and what adjustment the body angle is at (timing slot/sensor position). :?

So, there is no accurate answer for your engine in setting Trigger Angle except what you determine through testing to be correct — for either system. To assume a certain reported value also assumes the ignition has not been touched in 30 years. :lol: Also realize the Trigger Angle will change if you change any of the parameters listed above and will need resetting in TS. I strongly suggest you do not use a value anyone else has used, as it is likely or probable to be different on your specific engine. I hope that helps!

By choyr
I believe if someone has a picture of ignition log of a working 24 tooth NE with G1 or G2 (dual teeth), then we can have a better discussion. For a missing tooth, that is easier since there's no problem with the NE signal.
I dont have the ignition log sample now but I will try next week.

Just to verify for the missing tooth, do you remove that tooth which is aligned to the VR sensor when cylinder 1 is in TDC, and then put trigger angle to 0? The distributor can be adjusted so I can select which tooth to shave if I will go to that route. I really want to use the stock distributor but if a missing tooth is better, then I have no choice. The car will be used in tracks so constantly revving up to 8000 should be no problem.

By stum
Hi Choyr,

Someone with more experence that me can probably give a more correct answer than me, but from my experence so far I do not deleive it makes a difference.

The only thing that I have taken on board when I modified mine was to make sure that the missing tooth was not around a TDC event when Speedie would be doing other stuff, like firing a plug.

Since mine is a dizzy, I have played with a number of different offests, as each timing event is 720/6 = 120deg apart. so I have tried (-)186 + 120 = (-)66 deg offset, and (-) 186 - 120 = (-)306 deg offset.

The engine behaved the same (that I could tell in the shed. same timing light events, same easy start....... There will be an effect on fule, but since Im not sequencial, this has a lesser effect.

Im still on the hunt to find out why the engine is limiting at 6000RPM. Ive been throught the menues, and I have not been albe to find any thing yet.
- rev limit set at 7000rom
- Flat shift - OFF
- Lauch control - OFF
Looked at IGN timing and Fule table, nothing strange there.

I will have another play tomorrow. Looking at trigger edge, filtering and Reset every sync (this is the only are I have not had a good look/play). Unfortunalty I can not test by my self, my arms are not long enough to use the timing light and start/run the truck.

This hopefully will cut down on the scatter of the timing. 24/1 setting was much tighter. But should not make any difference.
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