pre-turbo?
Again, I'm not an engineer, so.....
A turbo is similar in some ways to a jet engine, right? If you induce disturbed airflow to a jet engine's compressor stage (basically what our turbos do as I understand it - compress the air to make it more dense in the combustion chamber), you'll get a compressor stall as the blades cavitate where the airflow isn't smooth. Generally, if we've induced the stall, or chug as we call them, it's no big deal because we know what caused it and we don't do that maneuver again. If it's something we're supposed to be able to do, then there's a problem and the plane's grounded until maintenance can figure out what's causing the chugs.
Now, if you were to install a vortex generator in the engine intake, I'm thinking you'd get constant chugging - not a good thing.
Chugs are bad because they cause high EGTs, can cause the turbines to overspeed and can cause vibration/stress damage to the compressor blades, ultimately leading to engine failure and possibly a fire. Again, bad.
So, putting some type of vortex generator pre-turbo MIGHT make the air flow around corners better (I'm very skeptical here) but it would be disturbed airflow when it hit the turbo blades and cause irregular performance of the turbo. Smooth airflow, on the other hand may have some parasitic drag from the intake pathway, but overall, the smooth flow into the turbo will provide more performance than the disturbed flow.
Of course, I could be totally out to lunch. Wouldn't be the first time. In either case, I'm spending my $60 on bicycle bombs, not this gaget.
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