Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe (11th)

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Fred
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by Fred »

Andy, can you tell me the range of timing marks that your pulley has? I ask because we'll need to differentiate between DIS default timing and whatever we do. Ideally we'll need two check points besides the 10btdc marking. If the timing marks go from 0btdc to 20btdc that would be ideal, however 5-15 would also work. We'll set it to 10btdc in the code for the first 1500RPM then X higher than that for the second 1500 (up to 3k), then X lower the rest of the way. This should create a retard limiter effect to keep you safe while testing :-)

Can you please commit your config changes and push them to a temporary branch so that I can tweak them to work with DIS. Do that like this:

Code: Select all

cd src
git add .
git commit -m "Temp config commit for Fred." .
git push
You'll need a fork of the firmware on there in order to push like that, and to have it set as your origin in your .git/config file.

Lastly, what is the polarity of the bypass signal requirement? Ideally it would be processor low by default and processor high to enable FreeEMS controlled timing. Same goes for the EST signal too, ie, trailing edge of processor high (processor goes low) = fire. If you used an XOR and those signals match, then it will be straight forward to configure them correctly in hardware.

If we get this sorted out ASAP maybe we can work together on the phone tomorrow to get it running properly right there and then. If you have time after dinner to push the config and answer the questions that'd be awesome, if not, no stress. I'm going out for dinner too and may be in no shape to do any work :-)

Fred.
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by DeuceEFI »

Fred,
My 3.1L engine doesn't have a timing tab from the factory, so I'm going out to parts stores in search of one to use (read this as modify to fit). I should have something setup by this evening my time. Right now the GM procedure was to see the timing mark as straight down with the DIS in limp home mode (10 degrees BTDC) and that is where I see it with the timing light.

I have forked freeems-vanilla and pushed my changes to my fork.

The Bypass output needs to be 0Vdc while cranking and +5vdc while running, I do have this output going through the XOR, so we have the ability to change the polarity if needed.

When the EST (timing advance) signal goes from HI to LO, that transition = fire and here again, I have that going through the XOR so we have the ability to change the polarity if needed. So I think we are on the same page in regards to this event.

I'll ping you on IRC once I get the timing tab installed...
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by Fred »

Great progress! :-) I'll have a look at your config soon and maybe start on a special test version just for you <3

As for timing tabs, some have the scale on the pulley and the fixed point on the engine. I'm pretty sure it will work correctly, but we need to verify it this first time.
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by DeuceEFI »

Saleae trace of DIS 3x output versus the MAX9926 output.
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Input_Output_at_MAX9926.logicdata.zip
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by DeuceEFI »

3x Reference Pulse Input to MAX9926 versus Output from MAX9926 via xoscope.

Edit: uploaded correctly rotated photo.
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Correctly rotated photo
Correctly rotated photo
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by DeuceEFI »

First logic trace of ignition test
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ignition_firstTest.logicdata.zip
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by DeuceEFI »

Sweep from 0 to 6000 RPM back to 0, then back up to 1500 RPM
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zeroTo6kTozero_backTo1500.logicdata.zip
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by DeuceEFI »

Sweep from 0 to 6000 RPM back to 0, then back up to 3500 RPM

T3 stays LO until 1500, then goes HI
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zeroTo6kTozero_backTo3500.logicdata.zip
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by DeuceEFI »

Traces from both forks of freeems-vanilla, I couldn't keep the engine running with the DeuceCoupeTempTimingHooray firmware, it kept dying. I haven't diff'ed the files to see what changed, but I am noticing that the CAS signal looks like crap on the DeuceCoupeTempTimingHooray trace so I'm thinking the DB37 is giving me fits...

I'm going to get a logic trace of the factory ECU on the Oldsmobile that I used earlier to create the xoscope screenshots so we have an apples to apples look at how the port T2 should behave.
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DeuceCoupeTempTimingHooray.logicdata.zip
This is a trace shows the Deuce running the DeuceCoupeTempTimingHooray firmware and settings
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DeuceCoupeTempBranch.logicdata.zip
This is a trace shows the Deuce running the DeuceCoupeTempBranch firmware and settings
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Re: Engine #11 Andy's 1996 GM 3.1L V6 in a 1932 Ford Coupe

Post by DeuceEFI »

Here are some screenshots of Reference Pulse (Green Trace) versus the EST signal generated by FreeEMS (Blue Trace) at just off idle and revved up to about 2500 RPM.

It was easy to start and never died until I turned the key off :-)

Video link: http://youtu.be/f8b5pIj4z0M
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Original factory ECU controlling DIS at Idle
Original factory ECU controlling DIS at Idle
xoscope view revved up
xoscope view revved up
xoscope view just off idle
xoscope view just off idle
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