Setting timing in MS problems.
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Setting timing in MS problems.
Ok guys, so you all know me and that I've read the megamanual many times, but this one has really got me stumped.
Anyways, I've got megasquirt set to show 10 degrees BTDC.
CAS is turned all the way in the retarded direction.
AFRs are fine.
I can't get the timing mark to get anywhere near the 10 degree mark without the engine running poorly and dying. It seems about at 20 BTDC I can't retard the timing anymore and the engine dies. I've got my trigger angle at 89 degrees, if I go up to 90 with or without the +22.5 addition it will die immediately.
What's odd is before this I threw the stock ECU back in and attempted to start it. Before that my trigger angle was 74 degrees.
What am I missing?
Edit: I am able to reach timing marks with the 22.5 addition at the mid 70 trigger angles. Is this a viable solution?
Anyways, I've got megasquirt set to show 10 degrees BTDC.
CAS is turned all the way in the retarded direction.
AFRs are fine.
I can't get the timing mark to get anywhere near the 10 degree mark without the engine running poorly and dying. It seems about at 20 BTDC I can't retard the timing anymore and the engine dies. I've got my trigger angle at 89 degrees, if I go up to 90 with or without the +22.5 addition it will die immediately.
What's odd is before this I threw the stock ECU back in and attempted to start it. Before that my trigger angle was 74 degrees.
What am I missing?
Edit: I am able to reach timing marks with the 22.5 addition at the mid 70 trigger angles. Is this a viable solution?
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From: Chicago. (The less-murder part.)
It seems a bid odd, but that's exactly what the Addition dropdown box is there for. When I was running a CAS (adjusted to 10° base on the stock ECU) my trigger angle was 76.
I'd suggest that as a test, you set the Fixed Angle to 10 and then run the RPMs up from idle to at least 5 or 6k, and verify that the mark does not significantly drift. It'll jump a little, but we don't want it retarding itself by 10 or 20 degrees. This test will check for excessive latency in the CAS decode circuit. If it's OK, then you're OK.
I'd suggest that as a test, you set the Fixed Angle to 10 and then run the RPMs up from idle to at least 5 or 6k, and verify that the mark does not significantly drift. It'll jump a little, but we don't want it retarding itself by 10 or 20 degrees. This test will check for excessive latency in the CAS decode circuit. If it's OK, then you're OK.
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From: Cypress, TX
Update: FAIL
The car runs like a dog with the trigger angle set at 71 and a 22.5 addition. It hits a wall (albeit a soft one) at 4k rpms and drives worse than a base greddy kit with the timing retarded. This is with the timing mark lined up at 10 degrees though! What gives?
The car runs like a dog with the trigger angle set at 71 and a 22.5 addition. It hits a wall (albeit a soft one) at 4k rpms and drives worse than a base greddy kit with the timing retarded. This is with the timing mark lined up at 10 degrees though! What gives?
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