Product images and videos are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Exhaust› Exhaust Pipes, Systems and Components

Ktuned

3-Inch 304 Stainless Steel Downpipe

Name: 3-Inch 304 Stainless Steel Downpipe
Brand: Ktuned
SKU: KRH-9TH-K24

$604.70

SKU: KRH-9TH-K24

Free Shipping over $200

$100 Minimum Order

Non-Returnable Item

DIY PRO SHOP

Moderate — 2–4 hours

Overview

The K-Tuned Downpipe Header is a 3-inch exhaust component designed for the 2012-2015 Honda Civic Si.

Constructed from mandrel-bent T304 stainless steel, it features a wide bellmouth inlet and a two-piece bolted design for secure assembly. This downpipe includes a vibrant flex pipe for durability and performance, along with two O2 bungs for easy accessory integration. It is offered exclusively in a non-catalytic converter version, intended to maximize power output.

Show original supplier description

The K-Tuned 9th Gen Civic Si Downpipe is engineered to enhance exhaust flow for the 2012-2015 Honda Civic Si models, including both 2-door and 4-door variants. It replaces the restrictive factory catalytic converter with a free-flowing 3-inch, T304 stainless steel pipe. The downpipe starts with a cast stainless steel housing that provides a smooth transition from the exhaust manifold to the 2-bolt exhaust flange. The 3-inch diameter T304 stainless steel piping is TIG welded and routed carefully to clear the factory subframe and sway bar. For enhanced sensor compatibility, the cast housing is equipped with two O2 sensor bungs. One is intended for the primary O2 sensor, and a second is included for an accessory sensor, complete with a plug for unused ports. K-Tuned includes all necessary hardware for installation, such as an O2 plug, serrated M8 nuts, an M8 bolt, and an M8 washer for the housing-to-head connection, though some original hardware may be reused. It is highly recommended to upgrade the rear engine mount to a Hasport rear mount to limit movement. This downpipe is designed to mate perfectly with the K-Tuned 9th Gen 3-inch exhaust system, potentially leading to further performance gains when used as a complete system.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

Brand	Ktuned
Part Number	KRH-9TH-K24
Category	Exhaust

Videos

K-Tuned 9thGen Civic Si Exhaust Review by RickSpecd

9th Gen Civic Ktuned 3" Catback Exhaust Install!

5,000+ Trusted brands

1M+ Enthusiasts

5M+ Parts sold

(760) 282-4645 hello@motormia.co

Buy with Confidence

Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

View Full Return Policy

Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

View Full Shipping Policy