[Pekka Berkeles]

Googlasin pitkästä aikaa Corvette-foorumia, ja siellä oli pari mielenkiintoista kommenttia (kaiken töhnän seassa):

"I have heard people complain of surging from just about every type of aftermarket unit out there. Even running the stock LS3/7 air intake and adding a Vette-Air scoop can cause turbulence(I had bad surging, and CEL, with this MOD and it took a lot of time to correct the problem by fabricating a diffuser to prevent the incoming air from being forced directly into the mouth of the air breather. I found that using the Attack Blue filter in the stock housing did not straighten the airflow nearly as well as the OEM Donaldson PowerCore element). GM has experienced customers complaining about surging(and CEL) on completely stock cars. The TBS instructs the tech to not mess with trying to diagnose the problem if the car has any type of aftermarket air breather modifications. If the car has no air breather MODs, then the tech is instructed to make sure there is no air leaks between the shroud and the bumper beam and even instructs the tech to tape over the holes in the bumper beam to prevent air intrusion directly to the mouth of the air cleaner housing."

Ja toinen:

"As only part of my engineering background dealt with air control I think I remember the part about turbulence in a closed system being a function of shape and directional speed of airflow. 70 MPH is about 1500 RPM and only requires about 165 CFM on a LS3. That's roughly 4 CFM per square inch of filter face area. The stock LS3 filter is about 3-4" thick with around 100 passages per square inch, which gives plenty of time to difuse turbulence on direct inlet airflow at most any speed and create nearly linear airflow which is then directed by the housing shape prior to passing the MAF.

The surging happens when that airflow is not evenly distributed and/or perpendicular to the face of the filter. Pre-filter turbulence causes differential pressures post-filter in the same manner as putting your hand out the window to experience the buffeting effect. GM resolves the problem by eliminating direct turbulent sources. Vararam takes in air and straightens it slightly, then dumps it into an expansion chamber prior to the filter to slow the speed, which effectively kills the turbulence. A propped shroud works kinda OK at low vehicle speeds opened wide and higher speeds with a narrower opening to reduce turbulence."