A little data from my zero clearance K04 S4 for comparison, if possible. Graphs updated.
#1
A little data from my zero clearance K04 S4 for comparison, if possible. Graphs updated.
I wanted to compare airflow #s from Jordan's car and mine. We both have 83mm maf housings stuck in a stock airbox. My airbox has been modified so that there is a smooth transition into the maf housing. We both have RS4 intercoolers and I installed an MBC to as closely as possible mimic his boost curve. I was getting a 23psi spike tapering to 21.5 by 6300 and finally 20.5 by rev limit. Setting the MBC to a 21.5 taper to rev limit created too big of a boost spike.
I suck at the excel and haven't gotten MarkP's templates working yet, but I think we can get by with my grafs.
<img src="http://pictureposter.audiworld.com/72863/2nd_attempt.jpg">
<img src="http://pictureposter.audiworld.com/72863/3rdattempt.jpg">
I suck at the excel and haven't gotten MarkP's templates working yet, but I think we can get by with my grafs.
<img src="http://pictureposter.audiworld.com/72863/2nd_attempt.jpg">
<img src="http://pictureposter.audiworld.com/72863/3rdattempt.jpg">
#3
I assume based on your starting IATs that ambientt temp was between 40F and 45F. Here are some....
Here are mine from 45F ambient temp (actually might have been closer to 21.5 PSI at rev limit instead of 20.5 PSI but best I have for recent logs in a given temp AFAIK):
Our IATs are damn near identical (25F-30F delta)....
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage310-21-0610445FIAT.gif">
Your MAF readings seem higher, but really hard since cars differ so much in MAF transition and such....
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage310-21-0610445FMAF.gif">
Our IATs are damn near identical (25F-30F delta)....
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage310-21-0610445FIAT.gif">
Your MAF readings seem higher, but really hard since cars differ so much in MAF transition and such....
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage310-21-0610445FMAF.gif">
#5
And here are graphs from 55F when I was running your boost curve almost exactly....
MAF is ~10 g/s lower, you flow ~10% more assuming all else is equal and our MAF readings are both reading similarly (no inflation or deflation due to transition and such)...
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage310-7-06MAF.gif">
IAT delta is maybe a touch less due to slightly lower boost, dunno, too hard to tell, seems more like 25F...
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage310-7-06IATs.gif">
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage310-7-06MAF.gif">
IAT delta is maybe a touch less due to slightly lower boost, dunno, too hard to tell, seems more like 25F...
<img src="http://img.photobucket.com/albums/v654/DocSlow/HomebrewStage310-7-06IATs.gif">
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