I changed my air filter on my '06 S2000 not because of restriction but because it was six years old. The inside of the intake air tube was clean as if it was new. I even took a white glove to see if I could find any dust, I couldn't see any. The old filter was a Wix I put in when I bought the car back in 2010. This time I went with a Honda air filter, don't know if I'll still own the car in another 90+ k miles, but if I do I'll take pic's of it too.. This Wix held up very well and I would not heasitate to use one again.
I put a restriction gauge on my S back when I got the car and it still didn't show any restriction after all of those miles. We have driven our S over 105,000 miles all over the western US(I think 13 states) we also drive our S year round and we take back roads whenever we can.
Old Filter
Here are all the pics I took
http://s188.photobucket.com/user/rodrounds/library/air filter 90000 miles?sort=2&page=1
And here is my air filter restriction gauge
ROD
I put a restriction gauge on my S back when I got the car and it still didn't show any restriction after all of those miles. We have driven our S over 105,000 miles all over the western US(I think 13 states) we also drive our S year round and we take back roads whenever we can.
Old Filter
Here are all the pics I took
http://s188.photobucket.com/user/rodrounds/library/air filter 90000 miles?sort=2&page=1
And here is my air filter restriction gauge
ROD