yup, cylinder airmass is cylinder airmass, no matter where it is
yup, cylinder airmass is cylinder airmass, no matter where it is
But surely one is a mass & the other a mass flow rate?Originally Posted by redhardsupra
2004 Monaro CV8 - 80mm BBK throttle body - 42lb Injectors - 1.8 Rockers - CAPA Long-Tube Headers- SLP Exhaust - Vortech Centrifugal S/C @ 7PSI- CAPA Intercooler - Bilstein Shocks - Wilwood 6-Pot/4-Pot Brakes - TyreWatch Monitoring - LC-1 Wideband - KAAZ Diff - Racelogic - 480RWHP
That was something that was supposed to be fixed the last time I asked. I'll PM your post to Blacky and see what he remembers. But, B4901 refers to the GM.DYNCYLAIR_DMA pid, which reports out in grams/cylinder. However, the y-axis is scaled based on grams/second of airflow as if it were supposed to be using the GM.DYNAIR or SAE.MAF pid. So, logging will always show the first cell being looked up given the fact that I have yet to see cars runnig 5 grams/cylinder. N/A it's more like 0.88 grams/cylinder.
Cheers matey
2004 Monaro CV8 - 80mm BBK throttle body - 42lb Injectors - 1.8 Rockers - CAPA Long-Tube Headers- SLP Exhaust - Vortech Centrifugal S/C @ 7PSI- CAPA Intercooler - Bilstein Shocks - Wilwood 6-Pot/4-Pot Brakes - TyreWatch Monitoring - LC-1 Wideband - KAAZ Diff - Racelogic - 480RWHP
ok, i took a shot in a dark and apparently i missed :(
if the labels are messed up, you can't help it. that's why i more often look at units than labels. if it's like 5-500g/sec that's airflow, if it's 0.15-1.4g/cyl that's airmass.
OK, I have logged GM.VETABLE_DMA. Something wierd (possibly a coincidence as I modified the tune file & uploaded to the PCM prior to logging), but for the first time, I have recorded values above 5 psi (137kPa) at around 145kPa.
Anyhow in reference to your spreadsheet, the recorded data for 5864rpm/145kPa is:
IAT = 18ºC
ECT = 90°C
Air Mass = 1.77grams/cylinnder (GM.DYNCYLAIR_DMA)
VE Table Lookup = 3.45371 g*K/kPa
The g*K/kPa value from the boost table (6000rpm/145kPa) = 3.87. Presumably the difference between 3.78 & 3.45371 is the proportional to the difference in the rpm value.
So putting these figures into the spreadsheet, the values for a 0 factor are 291.15°K & 1.72 grams/clyinder. Do I then compare 1.72 against 1.77?
What does this mean for tables B4901 & B4902? SHould I be setting the factors nearer to IAT?
Phew.
Edit: Is is at all possible to ever get past 10 grams/second on B4901?
Last edited by NAH; January 29th, 2007 at 11:45 AM.
2004 Monaro CV8 - 80mm BBK throttle body - 42lb Injectors - 1.8 Rockers - CAPA Long-Tube Headers- SLP Exhaust - Vortech Centrifugal S/C @ 7PSI- CAPA Intercooler - Bilstein Shocks - Wilwood 6-Pot/4-Pot Brakes - TyreWatch Monitoring - LC-1 Wideband - KAAZ Diff - Racelogic - 480RWHP
That spreadsheet was developed to merely visualize the effect that table had on the Charge Temp Factor. I don't have the first clue on the right way to set the values in there. As you reduce the factor, the swing in charge temps increases. Likewise, if you reduce the factor, the swing isn't as great...but then again, the airflow numbers look awefully low.
With that table referencing grams/cylinder, you'd need to be running a great deal of boost in order to get out of the first cell. That's why I think either the pid referenced is wrong OR the scale on the side of the table is wrong. As of my latest version of 7.3.2, it still hasn't been fixed. Hopefully, 7.3.3 has the fix. But, I'm not 100% on that one (yet).
Nope, I'm using 7.3.3. Does sound like the scale is suspect.
2004 Monaro CV8 - 80mm BBK throttle body - 42lb Injectors - 1.8 Rockers - CAPA Long-Tube Headers- SLP Exhaust - Vortech Centrifugal S/C @ 7PSI- CAPA Intercooler - Bilstein Shocks - Wilwood 6-Pot/4-Pot Brakes - TyreWatch Monitoring - LC-1 Wideband - KAAZ Diff - Racelogic - 480RWHP
The PID in B4901 is incorrect.
NAH, could you post your log? i might be able to help you
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