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Injen 17-20 Honda Civic Si 1.5L Turbo (Sedan Only) 3in Cat-Back Stainless Steel Exhaust

SKU: INJSES1581TT

Exhaust Systems

INJ Catback Exhaust...

Injen 17-20 Honda Civic Si 1.5L Turbo (Sedan Only) 3in Cat-Back Stainless Steel Exhaust

SKU: INJSES1581TT

Exhaust Systems

INJ Catback Exhaust...

A$2,491.58
LOW STOCK! Est Ship 3-5 days. HURRY! LOW STOCK. This item is in limited stock at one of our distribution centres. The ETA is the approximate time required to prepare your order for dispatch.
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Description

The Injen Technology engineers are experts when it comes to performance, PERIOD. From Cars to Trucks to Powersports, Injen has a variety of exhaust systems to choose from. All of Injen Technology Performance exhaust systems are constructed from mandrel bent stainless steel tubing Mandrel-bending ensures the tubing maintains its shapes and size throughout the entire length, providing smooth, unrestricted airflow. From the Investment cast flanges to the custom hangers, all Injen exhaust systems are 100% TIG welded and handcrafted in the USA and include all tubing, mufflers, and hardware necessary for a hassle free installation. Each system is uniquely designed to offer an aggressive sound that brings out some massive power. Like all other Injen products, the Injen exhaust systems are proudly built in Pomona, CA.

Product Overview

The Injen Technology engineers are experts when it comes to performance, PERIOD. From Cars to Trucks to Powersports, Injen has a variety of exhaust systems to choose from. All of Injen Technology Performance exhaust systems are constructed from mandrel bent stainless steel tubing Mandrel-bending ensures the tubing maintains its shapes and size throughout the entire length, providing smooth, unrestricted airflow. From the Investment cast flanges to the custom hangers, all Injen exhaust systems are 100% TIG welded and handcrafted in the USA and include all tubing, mufflers, and hardware necessary for a hassle free installation. Each system is uniquely designed to offer an aggressive sound that brings out some massive power. Like all other Injen products, the Injen exhaust systems are proudly built in Pomona, CA.


Features and Benefits

  • Designed And Made In Pomona; CA
  • Fits Civic Si Sedan models ONLY
  • Center exit design fits with factory rear valance
  • Dyno Proven gains of up to 11 hp and 10 lb?ft of torque
  • Full 76MM piping made from premium 304 SS Mandrel-Bent Tubing
  • Features Injen's integrated resonator for crisp, clean sound
  • Beautiful dual 4.0"burnt titanium exhaust tips
  • Stainless Steel Investment Cast Flanges For a Fast and Easy Install
  • Hand Crafted and TIG Welded to Perfection for Strength and Durability
  • No Cutting or Welding Required
  • Premium Stainless Steel Hardware and Hangers
  • If you're looking to improve sound, power, and looks then this is the system for you!
  • Manufactured in Pomona, California USA

Product Details

Catalytic Converter Quantity:0
Compatible Throttle Controller:PT0018B
Description:Cat-Back Exhaust System
Exhaust System Connection:Flanged
Exhaust Type:Cat-Back
Exit Position:Straight Out Back
Finish:Polished
Grade Type:Performance
Hangers Included:Yes
Hardware Included:Yes
Inlet Inside Diameter:3.000 in.
Material:304 Stainless Steel
Muffler Body Diameter:4.5
Muffler Body Length:15
Muffler Body Material:304 Stainless Steel
Muffler Body Shape:Round
Muffler Flanged Inlet:No
Muffler Flanged Outlet:No
Muffler Let Size:3
Muffler Outlet Quantity:1
Muffler Outlet Size:3
Muffler Quantity:1
Part Number:injSES1581TT
Pipe Material:304 Stainless Steel
Primary Pipe OD:3
Prop 65 (C, R or CR):CR
Prop 65 - Short Label:prop65_warning.jpg
Prop 65 Yes/No:Yes
Secondary Pipe OD:3
Stepped Pipe Diameter:No
Tail Pipe Diameter:3.000 in.
Tail Pipe Material:Burnt Titanium
Tail Pipe Outlet Outside Diameter:4
Tail Pipe Quantity:2
Tip Diameter:4.000 in.
Title:Injen Performance Exhaust System
Tubing Diameter:3.000 in.
WARNING CA Proposition 65 Message:This product can expose you to chemicals including Chromium; Nickel and Cobalt; which are known to the State of California to cause cancer.
WARNING CA Proposition 65:Yes
Y-Pipe Included:No

Part Type

Exhaust System Kit

Data: v4.2 - Upd: 2026-10-13 23:10:16

Features

  • Beautiful dual 4.0"burnt titanium exhaust tips
  • Center exit design fits with factory rear valance
  • Designed And Made In Pomona; CA
  • Dyno Proven gains of up to 11 hp and 10 lb?ft of torque
  • Features Injen's integrated resonator for crisp, clean sound
  • Fits Civic Si Sedan models ONLY
  • Full 76MM piping made from premium 304 SS Mandrel-Bent Tubing
  • Hand Crafted and TIG Welded to Perfection for Strength and Durability
  • If you're looking to improve sound, power, and looks then this is the system for you!
  • Manufactured in Pomona, California USA
  • No Cutting or Welding Required
  • Premium Stainless Steel Hardware and Hangers
  • Stainless Steel Investment Cast Flanges For a Fast and Easy Install

Specifications

Product Attributes - UPC
843115027230
Product Attributes - Brand
Injen
Product Attributes - Notes
Tips are polished with a burnt edge.
Product Attributes - Tip Cut
Slant
Product Attributes - Quantity
Sold as a kit.
Product Attributes - Part Type
Exhaust Systems
Product Attributes - Tip Shape
Round
Product Attributes - Tip Finish
Burnt
Product Attributes - Exhaust Type
Single
Product Attributes - Product Line
Injen Super SES Stainless Exhaust Systems
Product Attributes - System Style
Cat-back
Product Attributes - Tip Included
Yes
Product Attributes - Tip Material
Titanium
Product Attributes - Tip Quantity
2
Product Attributes - Exit Location
Rear center
Product Attributes - Muffler Style
Perforated tube
Product Attributes - System Finish
Polished
Product Attributes - Inlet Quantity
1
Product Attributes - Muffler Finish
Polished
Product Attributes - Tip Edge Style
Rolled edge, single-wall
Product Attributes - System Material
304 stainless steel
Product Attributes - Muffler Included
Yes
Product Attributes - Muffler Material
304 stainless steel
Product Attributes - Muffler Quantity
One
Product Attributes - Hardware Included
Yes
Product Attributes - Special Attention
It is illegal to install parts or components that bypass, defeat, or render inoperative the manufacturers’ technology and design necessary to reduce vehicle emissions to meet state and federal Clean Air Act standards.
Product Attributes - Muffler Configuration
Single inlet/Single outlet
Product Attributes - Tip Outlet Size (in.)
4.00
Product Attributes - Tailpipe Diameter (in.)
3.00 in.
Product Attributes - Manufacturer's Part Number
SES1581TT
Product Attributes - Catalytic Converter(s) Included
No
Product Attributes - Intermediate Pipe Diameter (in.)
3.00 in.

Reference Information

Brand Name/s Injen
StreetFX SKU injSES1581TT
SFX Item ID 4243163
Supplier Item Code 4243163
Manufacturer SKU SES1581TT
Manufacturer UPC 843115027230
Alternative References 1.5L, 3in

Brochures

Compatibility

Application Data
  • UniversalNo
    MakeHONDA
    ModelCIVIC
    SubmodelSI
    Beginning Year2017
    Ending Year2020
    Engine TypeL4
    Liter1.5
    CC1497
    Engine Size1.5L/1497cc
    Engine FamilyHonda/Acura 4-cylinder
    Body StyleCoupe
    TransmissionManual
    DrivetrainFWD
    Application NotesAspiration: Turbocharged. Fits Civic Si Sedans Only
  • UniversalNo
    MakeHONDA
    ModelCIVIC
    SubmodelSI
    Beginning Year2017
    Ending Year2020
    Engine TypeL4
    Liter1.5
    CC1497
    Engine Size1.5L/1497cc
    Engine FamilyHonda/Acura 4-cylinder
    Body StyleSedan
    TransmissionManual
    DrivetrainFWD
    Application NotesAspiration: Turbocharged. Fits Civic Si Sedans Only

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