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ECMlink new to sd values in gray ?

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In my case, my car HATES on me and dies. OMG I can try to get it lower but no matter what I did 34 was about as low as I could get it. Would it make sense that the engine is having to ingest more air to keep the car running because of the "lope" of the cam overlaps lets more than normal intake charge to get on out the exhuast valve before it is closed and ready for combustion??? In my SBC's with big cams, I always have to idle her up or it won't run, so I guess I am feeding them more air (and fuel) just to keep them idling.
 
Yea that's exactly what I meant by I wasn't focusing on the relevant pieces... The overlap makes sense why more would be ingested, although not necessarily used at combustion, since it escapes into the exhaust (i guess).

I am not surprised the cams keep it from wanting to idling down to 750rpm. At 34 isc position I would say your close enough for the ISC to keep things in check. Out of curiosity what kind of airflowperrev's are you getting? I would be totally happy with 34 isc position having cams. Some people cant get it anywhere close so I am still curious what kind of issues arise for them.
 
I am at 34 in airflowperrev not ISC position. I haven't logged that in quite a while, could look at a old log. I think I still capture it just don't display it.
And OP, keep the questions coming. Sorry to get sidetracked! :ohdamn:
 
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The Airflowperrev calculation is just Airflow divided by RPM. It will be affected by cams (lift and duration) and RPM. I also noticed a positive change in it once I installed a jmf drag. I would expect anything increasing volumetric efficiency would increase Airflowperrev.

The ecmlink wiki also gives different expected values for V2 vs V3, so there must be a difference in the way it's calculated between the 2 programs.

Edit: From the wiki
Airflowperrev- This is literally airflow divided by RPM. It represents how much air is flowing into each cylinder per firing event. It's useful for a number of things, such as checking that your airflow at idle is roughly where it should be (around 0.28 g/rev when displayed with the V2 app, 0.24 gm/rev with displayed with the V3 app).
 
Right, but its a ratio. As RPM goes up, so does the amount of airflow into the engine. Thus the ratio should be fairly constant when idling. Mine idles at .27 at 1100 rpm and .27 at 750 rpm. He mentions in the video the number comes from the swept volume of the cylinders in a revolution. Thats why a 2.3 L is slightly higher. I suppose if cams are flowing extra air through the head due to overlap that would explain why values would go up as well.
 
Anyways, I guess that with SD I wouldn't focus on any values given as "recommended." Clearly these cars can perform well on SD but they are setup for a MAF and its no real surprise that certain parameters will vary when your changing the entire method of airflow metering.
 
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