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Help From A Datalogit User With Stock Air Flow Curves

Duncan

By Duncan,
in Engines & Forced Induction

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Duncan Grand Master

Duncan

Posted
Posted

Hi guys, strange results when I changed from stock to vg30/z32 AFM in the stagea.

While the old AFM was standard (as far as I know), the PFC was set to VG30/Z32.

With the actual Z32 AFM, it runs badly.

I am pretty sure the air flow curves for vg30 have been fiddled with along the line somewhere.

My VG30 settings are:

Volts 0 0.32 0.48 0.64 0.8 0.96 1.12 1.28 1.44 1.6 1.76 1.92 2.08 2.24 2.4 2.56 2.72 2.88 3.04 3.2 3.36 3.52 3.68 3.84 4 4.16 4.32 4.48 4.64 4.8 4.96 5.12

VG30 0 4 5 12 22 45 55 78 85 135 200 260 295 320 350 450 500 700 850 950 1200 1400 1600 2000 2200 2300 2800 3000 3200 3500 3800 4500

I found a partial screen shot from Trent which showed VG30 as

0 8 8 17 31 52 84 129 187 257 345

But the settings were not complete and I am not sure if they are stock.

Can someone with standard VG30 settings in their PFC and Datalogit please post up the correct standard values?

Full settings are here for reference:

air-flow-curves.xls

JonnoHR31 Grand Master

JonnoHR31

Posted
Posted

they're in the sample maps that come with fc-edit. if you dont have them then try re downloading the software. i'd upload a copy but dont have fc-edit on this computer

Duncan Grand Master

Duncan

Posted
  • Author
Posted

Excellent call, thanks mate.

I had been using the VH41 setting and the graph shows why it works....vh41 has the same AFM curve as VG30....

For reference, this is my vg30 curve vs standard afm vs standard vg30 curve vs vh41 curve.

afm_curves.jpg

JonnoHR31 Grand Master

JonnoHR31

Posted
Posted

No worries.

VH41 curve isnt the same as VG30, with that graph it'd be a much flatter line, higher airflow at low volts and lower airflow at high volts. Sounds like someones messed around with your afm tables a fair bit....

JonnoHR31 Grand Master

JonnoHR31

Posted
Posted (edited)

Found my copy of fc-edit and these are the standard settings for vg30 and vh41. You should be able to copy and paste these straight into fc-edit. Top row is VG30. At 2.08V both AFM's are flowing the same amount of air but below that the VH41 is flowing more and above that the VG30 is.

0 5 5 12 22 37 59 92 134 185 249 329 425 539 674 827 999 1197 1418 1655 1937 2246 2586 2961 3376 3835 4335 4883 5475 6114 6804 7546

0 5 13 25 40 59 85 117 159 210 274 344 426 526 635 758 906 1076 1268 1481 1716 1976 2277 2600 2992 3421 3854 4337 4847 5396 6015 6683

Edited by JonnoHR31
Duncan Grand Master

Duncan

Posted
  • Author
Posted

Excellent, thanks for checking this out. :cheers:

The numbers you provided above match what I got rom the default map for vg30 so that's good news.

No idea why everything else has been moved around...I'll clean them up over time, for now it just needs to run OK for a few weeks until a proper tune.

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