CARB Compliance / Exemption Warning: If you live in California and your application for this product is not CARB Compliant / Exempt, then you cannot purchase it for public highway or street use (in that case it could only be used for formally sanctioned race use on a racing vehicle that may never be used on a public highway or street). If your application is not CARB Compliant / Exempt and you're shipping to California, our system will let you know on the final checkout page.

IMPORTANT: This product does not include a throttle body. It is just an adapter. For a full throttle body upgrade kit please see our SiriMoto Big Bore Throttle Body Upgrade Kit product page.

• Basic kit to adapt a large bore throttle body to your factory intake manifold.

• Allows for easy fitment of larger throttle bodies.
• Dyno proven for the best results.
• Precision Lofted Port for uninterrupted air-flow.
• Precision machined adapter plates/spacers.
• Covered by SiriMoto's 1 Year Limited Warranty.

• Has an extra 1/8" NPT port (great for nitrous, vacuum/boost gauge, etc.).
• High quality silver zinc plated socket head cap screws.
• Includes 1/8" NPT Port Plugs and 8mm Hose Barb.
• 8mm (5/16") Kynar Male Union Included for coolant by-pass.
• All bolts and washers necessary for installation included.
• 6mm Hex Key included for easy installation.

SiriMoto kept usability in mind when designing the big bore adapters, taking NPT port-location, throttle body orientation, and ease of use into consideration during the entire design process. Also, when it comes to fitment the adapter is second-to-none, the CAD designed spacer is a snug fit with precision bore openings for optimal flow. Style and appearance was also of high importance, as the adapter plate features a brilliant anodized finish, giving your engine bay high ratings among performance enthusiasts.

2006 to 2011 Civic Si Application Features:

• Adapts to a Honda ZDX / J37 style throttle body.
• Includes two specially engineered SiriMoto Thermal Throttle Body Gaskets.
• 73mm opening on the throttle body side.
• 70mm opening on the intake manifold side (port matching on the intake manifold recommended).

2012 to 2015 Civic Si Application Features:

• Adapts to a Honda ZDX / J37 style throttle body.
• Includes one specially engineered SiriMoto Thermal Throttle Body Gasket.
• 73mm opening on the throttle body side.
• 65mm opening on the intake manifold side (to match OEM manifold port, although you can still port match if desired).

Intake Manifold Recommendations: The 2006 to 2011 Civic Si J37 ZDX Throttle Body Adapter Kit application will work best if you are using an RBC, RRC, K20Z3 Skunk2 Pro Series (with clearancing near manifold coolant port), or similar intake manifold. Skunk2 Ultra Series intake manifolds are not compatible with this product, nor is it compatible with 8th Gen Civic Si CT Engineering Supercharger Kits.

Tuning Info: Big Bore Throttle Body Upgrades allows much more airflow than your stock throttle body, ADJUSTING THE ECU CALIBRATION AFTER INSTALLING THIS PART IS REQUIRED. Without an ECU tune, your car may not drive correctly or get full power. To make these adjustments, a Hondata FlashPro is highly recommended. Feel free to give our knowledgeable tech department a call if you have any questions.