Take a look at the 96-98 (Silver) Civic compared to the 99-00 civic (Red)
http://en.wikipedia.org/wiki/Sixth-g...on_Honda_Civic
On the bottom of the bumper it a much smaller inlet for air on the 99-00.
What do you think. Would that make much of a difference?
I also was looking up CD numbers for the two different styles and found many variances on the web. Once I get it going I will have to do my own numbers.