Review on K&N Cold Air Intake Kit for ACURA/HONDA (RSX Type-S, Civic Si, Civic VI, Civic Type R): High Performance & Guaranteed Horsepower Boost (2000-2006): 69-1009TP by William Obong

Installs quickly and easily on a 2004 Civic Si - the hardest part was removing the factory system. Below 3500 rpm it is almost indistinguishable from the series, but after that it quickly gets louder. Nothing I'd definitely find uncomfortable (at least not with the stock exhaust), but there's a nice audible feedback when hard accelerating or downshifting to match the rpm. 5 hp I can not say noticeable. , although. Actually, I was mainly hoping for a slight increase in fuel consumption, but I installed it as soon as the temperature dropped, I changed summer tires to aggressive winter ones, so it's difficult to measure a significant difference. Due to the design of the Civic's engine bay I'm a bit concerned that it will get dirty pretty quickly and I'm thinking of one of the winter driving filter foils. I'll take a closer look when I install the plug heater next month.