SKU: 58938256636

Cold Air Intake System (06-11 Civic Si)

Sale price$233.37 Regular price$259.30
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Description

Cold Air Intake System (06-11 Civic 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

  • 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 resoce. 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.

View Install Guide HERE
Shipping Notes
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Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 58938256636

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Louisville, US
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Can't go wrong with Acorn for as long as they last!
Size: 12-13 Women/10.5-11.5 Men, Color: Charcoal
Acorn is just a great company all around. I had bought my husband these slippers over 20 years ago. They are still in great shape although the sole has worn in some places. But nothing's coming apart! However, I decided to replace them for him. His foot is 10.5 and they are a little hard to get on right away-of course, after over 20 years of having "worn in" the original pair, anything would feel tight. So I'm not holding this against them. They will relax with use. The only difference is that the original sole was black and these are tan. I think I would prefer the black, but since it's only being worn in the house, no big deal. My husband has really cold feet and these slippers never fail to warm his feet right up! He said they feel really soft to walk in and like the cushioning. They're not too heavy and fit him great! I have Acorn slippers myself that I've worn every single day in the house and outside to the mailbox too. They last.
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Michael
New York, US
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Very warm.
Size: 13.5-14.5 Women/12-13 Men, Color: Navy Blue
Very warm and comfortable. A little difficult to put on with the collared top.
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Great padding for comfort and terrific warmth. I bought a pair of Acorns 30 years ago and still have them. Updated to a new color and now feel the benefit of newer padding! I used the sizing listed for shoes and like the roominess for thicker sox. Well made and a joy to put on. (Wisconsin)
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