I got to reading this thread after searching for information on the often debated CAI, SRI, filter gains topics. I also got to reading an old article (with interesting data) on NICO see:
K&N Air Filter Review - Debunking the Myths (and why OEM is better) for the original.
Useful data (I think), more empirical than most comparisons, but I'm not sure I agree with the conclusions. So, I'm posting and possibly throwing gasoline on the campfire, but I am interested in what others thinks about the data and conclusions.
To be clear: air filters were being tested, not 370Z performance with various filters. I think this matters (in part), but doesn't change our abilities to draw conclusions; we simply need to consider how the differences in vehicles might affect what we can or cannot conclude. Here are the details:
"SCOPE:
This report presents the results of an ISO 5011 test of several air filters designed for the GM Duramax Diesel. The test was independently performed under controlled conditions using a $285,000 machine at Testand Corp of Rhode Island (manufacturer of the machine)."
Below are some of the relevant data: