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[DutchVDub]

So I was playing around with my new VAG-COM tonight and recorded this data. 



From what I'm reading here I'm showing: (this was in 3rd gear on an unnamed county road)
RPM: 6280
AirFlow: 227 gal/sec??
Timing: 26.3deg
Speed: 153km/h (95mph)
Boost pressure: 1770 mbar (25.6psi) ??

From what I understand my chip should peak at 20psi, its a GIAC 91/93 octane chip and its the only mod to the car besides a cat-back exhaust.  I'm also not sure if my Mass Air Flow reading is in gallons per second or some other unit of measure, the defined scale is g/s.

Anybody know?  Does this info seem correct for my car?  Its a 2000 S4 w/ a 6spd

[Giggidy]

I can't see the pic but the boost reading is right based of of 14.5lbs...

227 GPS doesn't seem right unless we're talking about a friggin jet engine though...

[DutchVDub]

Its grams/sec, so that makes more sense.

14.5?? whats that number from?

[p3u]

Its grams/sec, so that makes more sense.

14.5?? whats that number from?

Its actually grains per second for air flow.

Also the 14.5psi (1bar) is the atmospheric pressure at sea level, so up here its closer to .85-.9 bar depending where you're at.  Cars always will show that plus the amount of boost it is making.  In other words the 25.6psi the vag com shows is 14.5psi more then what boost you are making, so you are boosting 11.1psi.

[DutchVDub]

Its grams/sec, so that makes more sense.

14.5?? whats that number from?

Its actually grains per second for air flow.

Also the 14.5psi (1bar) is the atmospheric pressure at sea level, so up here its closer to .85-.9 bar depending where you're at.  Cars always will show that plus the amount of boost it is making.  In other words the 25.6psi the vag com shows is 14.5psi more then what boost you are making, so you are boosting 11.1psi.

That doesn't make sense though, 11psi is less than stock and I'm chipped

Ok, I got it figured out a bit better.  You subtract the rreading it gives you at idle, which at that point was .8BAR.  I was boosting 15.5psi or so.  It still seems low to me but I talked to Autobahn and they said that sounds right for my KO3's.

[MileHighAssassin]

Atmospheric Pressure (BAR/Barometric Pressure) is actually 14.7 at Sea Level. 

Here is a chart that shows elevatoin change and BAR/PSI Barometric pressures
http://www.engineeringtoolbox.com/air-altitude-pressure-d_462.html

This can change with temp and weather fronts but it gets you pretty close.


So you are seeing 1770 mmbar 
-at 5k feet barometric pressure is 632.5

So 1770 - 633 = 1137 mmbar
1137 mmbar = 16.4907908  PSI

Obviously this can change a little based on weather and your exact elevation.