Plenum Porting
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Plenum Porting
I had recently gone to a dyno machine and got it dynoed. 1996 12v Q after getting the results I along with the Mechanic running the dyno where puzzled by the results the hp drops in mid run then returns! If I can get the pic to work, take a look. The Audi mechanic in MN said that it is the plenum porting as it opens and closes during mid run.
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Yes, that is your variable intake manifold switchover, which happens around 4000 rpm.
<center><img src="http://pictureposter.audiworld.com/79119/dyno_run2.jpg"></center><p>
Seems like there is something wrong with your engine at 5500 rpm, however. Or is that what the AFC power curve is like? My AAH pulls hard all the way to the limiter.
Seems like there is something wrong with your engine at 5500 rpm, however. Or is that what the AFC power curve is like? My AAH pulls hard all the way to the limiter.
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The plenum is plastic. What's there to port? Just remove the thing!
Replace it with a silicone hose kit that puts away with the whole plenum for improved flow. Check the Abnormally Aspirated site linked in the right top corner of the forum for a hose kit.
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It's called an intake manifold.
The plenum has nothing to do with what you are talking about, it is made of plastic and cannot be ported - it can be replaced however. 
The intake manifold CAN be ported - STFA.
The intake manifold CAN be ported - STFA.
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