Hybrid Racing Cold Air Intake for 06-11 Civic Si

Our Hybrid Racing cold air intake for the 8th Gen Civic Si intake crowd came from a lot of design, testing, and revision on the platform. It works on a stock car, and it still makes sense when you stack on cams and exhaust. This is a Civic Si dyno proven intake, and we include graphs because talk is cheap. On our testing, we saw a 14hp peak gain and 9hp average gain over the stock air box. Compared to typical 3.5 inch cold air intake 8th Gen Civic setups, we usually saw another 2 to 3hp, plus a smoother curve, which you feel as better drivability, not just a bigger number.

The headline feature is the full silicone tube. This Silicone intake 8th Gen Civic Si uses 1/4 inch thick, fiberglass reinforced silicone that holds its shape under vacuum and does a better job keeping heat out than metal or plastic. Lower intake temps mean denser air, and denser air is power. Up front you also get a Civic Si velocity stack intake, a 6 inch velocity stack that reduces inlet restriction so your K20 can breathe easier, especially up top.

The injection molded bypass manifold does a few jobs. It mounts the factory MAF, hooks up the included silicone lines for the valve cover vent and bypass valve, and it adds a built in air bypass path if your filter gets soaked. That is the whole point of an Anti-hydrolock cold air intake. We dunk tested it by fully submerging the filter in a bucket and running the engine, and it idled and revved without hydrolocking. Still, don’t be the hero in deep water. No intake makes that a smart idea.

That manifold also helps knock down parasitic Helmholtz resonance, which is a fancy way of saying it calms down the weird dips some intakes create, so your powerband stays smoother. The kit includes a powder coated steel battery tray that relocates the battery in front of the transmission to clear the big piping, basically a Hybrid Racing battery relocation kit packaged with the intake. You also get a silicone upper radiator hose for clearance, plus silicone replacements for the OEM breather and bypass tube so the bay looks finished. All hardware is included. This is one of those Hybrid Racing Civic Si performance parts we actually run because it flat out works.

You’ll need tuning software like Hondata FlashPro, think FlashPro tuning intake Civic Si, after install. Run MAP based tuning only and do not run this on the factory calibration.