HR Cold Air Intake System (06-11 CIVIC FN SI)

Full Silicone Construction
Most powerful 8th Gen intake on the market
Built-In Air Bypass helps to prevent hydro-locking
Includes 3.5" velocity stack & filter
Includes battery relocation kit
Comes with couplers for large and small throttle bodies
Requires tuning software like FlashPro

Big tube, big power!
We spent countless hours designing, testing, and refining this design to ensure it was the absolute best intake available for the 8th Gen Civic Si platform. This intake is designed to make big gains on any setup, from totally stock to high-lift cams and huge exhausts. Dyno graphs are provided to show the intake's effectiveness against its competitors, but for example, we saw 14hp peak gain and 9hp average gain against the stock air box. Against competing 3.5" cold air intakes, we saw typical peak and average gains of around 2-3hp with a much smoother power band, meaning more power and better drivability.

The first and perhaps most obvious feature of this intake is its full silicone construction. The 1/4" thick fiberglass-reinforced silicone tubing is sturdy enough to withstand engine vacuum and insulates your intake charge better than any metal or plastic intake on the market. This leads to very cold intake air temperatures, meaning a denser air charge and more overall power. Another power-adding feature is the included velocity stack. This 6" velocity stack is designed to lower inlet restrictions and allow more air into your engine, again leading to a denser, more powerful inlet charge.

Built-in Anti-hydrolock bypass!
One very cool component in this kit is the injection molded air bypass manifold. This manifold serves a number of functions. It provides attachment points for the factory MAF as well as for the (included) silicone tubing that attaches to the factory valve cover vent and air bypass valve. It also has a built-in air bypass feature that allows air into the engine when the intake's filter becomes wet. This helps to avoid the dreaded hydro-lock that so many people normally worry about in heavy rain. We tested the bypass valve by totally submerging an air filter in a bucket of water and running the motor. Even when totally submerged, the engine idled and rev'd safely without hydro-locking. Of course, we still advise practicing caution when going through deep water in any car!

The biggest gain the bypass manifold provides is the reduction of parasitic Helmholtz resonance. The internal geometry of the air bypass manifold is designed to smooth out your power band. The end result is an intake that (on average) makes up to 14hp over the stock air box and even 2-3 more horsepower than any other 3.5" intakes. Also included with each kit is a powder coated steel battery tray that relocates the battery in front of the transmission to make room for this intake's massive piping. We also provide a silicone upper radiator hose to give better clearance than the stock radiator hose. Silicone tubing is provided to replace the OEM rubber valve cover breather and air bypass tube. This gives the engine bay a cleaner, more finished appearance. The kit includes all of the bolts, hose clamps, and hardware needed to install the intake and battery tray.

Tuning software required!
You will need a tuning software like Hondata's Flash Pro to tune the car after installation. This kit should be run using MAP tunes only and should not be used with the factory ECU calibration. Please note this system is sold as a complete kit and is not offered in pieces.