[cyrusthecirus33]

Bumping this for refresh. Im a coder, so I might look at this as soon as my speeduino arrives. I have a carbed V Twin and looking to use only crank wheel and map to determine phase, just like msx. Saw there is a bounty aswell

[theonewithin]

Bounty is gone. It was refunded as no one picked it up.

Use a MAP sensor and feed it into a VR sensor as suggested. Should work well enough.

It is what I will be doing as new wiring loom I am putting in will allow for the "stock" sensor to be wired in.

Hopefully it works so I can improve my spark energy.

[PSIG]

Several have used MAP pulses to signal cyl#1. However, keep in-mind it may be "less-useful" on some setups such as ITBs, which commonly lose most of the MAP signal as throttle increases. This loses the ability to re-sync. That's a separate issue to little signal while cranking, possibly requiring non-cycle-sync start with transition to cycle-sync. I say it that way as that doesn't mean it has to be a sequential setup to use cycle signal.

Alternatively, investigation of other signal sources with a MAP or pressure sensors are still possible, and I have seen modified throttle body signal placement (more of an air velocity detection), crankcase pulse on MAP sensor, and exhaust pulse sensing, for examples. There is a lot to explore, and thanks for your willingness to look at this general option! It would certainly be simpler than poking a hole for a sensor on the valve train or in the case to read a reduction gear.

David

[SyntaxErol]

Great to see this post have been ressurected, i have also posted a simmilar thread recently, trying to list what i have learned so far to assist the cause.

-We can use map sensor as a indexer for phase detection
-Map sensor data can be converted to a square wave form at its lowest point via a schmitt trigger, which can be fed to the cam sensor input. which than ecu will see it as a regular cam sensor output.
-microsquirt needs this cam data for only couple of turns of the crank. than it knows the "phase" since sequence of the phases will not ever change while engine is running. so map sensor's inability to produce good data at high rpms is not a problem. I assume speeduino works the same cause i can not think a good reason for any ecu to need constant cam phase detection signal. (Need more info here)
-Considering map sensor will also be used for metering instrument(for motorbikes and all ITB vehicles) on ITB mode (which still negate problems regarding high rpm map problems by switching itself to alpha-n at some point). We need to split map sensor output to feed 2 inputs on the ecu, one is cam input which will be fed trough schmitt trigger another one is fed to map input for ITB mode. This signal siplitting part of things is another part that i have no clue. how we can splitt the signal without degrading it or how much of a degradation will be acceptable etc. Really looking forward on oppinions about those.

[cyrusthecirus33]

This looks promising! Although Im sure you can somehow skip the whole re-sync thing in speeduino? Im sure it wouldnt work otherwise, well maby on a 1-cyl 4 stroke

[cyrusthecirus33]

I was wondering if it would be possible to set the second trigger in the missing tooth decoder - to "map", and then skip resync.
This could possibly be a feature request. And sorry guys havent been able to play around with either tunerstudio or the code, since my first speeduino is arriving next week
And maby skip a revolution before reading map so there enough vacuum in the intake.
Just a thought