By Integrated Engineering

Integrated Engineering Cat Back Exhaust System - Audi S4 B9/B9.5 3.0T

Regular price $3,319.95
Regular price Sale price $3,319.95
Shipping calculated at checkout.
Availability: In stock
SKU: IEEXCK5
Regular price $3,319.95
Regular price Sale price $3,319.95

The IE Catback Exhaust System for your Audi B9/B9.5 S4 incorporates our in-house engineered DroneTrap technology to deliver a truly aggressive exhaust note without any annoying drone or rasp. Engineered with cutting-edge design features, including mandrel-bent stainless steel, TIG welding, multi-point reinforcements, and oversized quad tips. Experience the elevated and enriched sound your S4 deserves.

IE's advanced DroneTrap technology captures the pulse waves responsible for your B9 3.0T engine's exhaust note and draws them into dual mathematically tuned resonators. The internal ports are engineered to resonate these waves against each other in a process that selectively cancels out those responsible for annoying drones. The remaining waves produce the deepened and enriched exhaust acoustics you love.

What is the point of a larger exhaust that looks stock? Stand out from the crowd with oversized 90mm quad slash-cut exhaust tips. These aggressive-looking tips fill the factory exhaust cutouts for that high-end sporty look.

Our catback design includes all sections to replace the factory exhaust tips, mufflers, and resonator up to the midpipes. Enjoy an unrestricted system that delivers the perfect exhaust note from your turbocharged V6 engine.

Advanced 3D scanning tools and cutting-edge software provide our engineers with a high-resolution digital model of the Audi B9 S4 chassis. This data is then used to maximize the exhaust size for flow and optimize all available space for the perfect catback fitment.

All piping is constructed of mandrel-bent T304L stainless steel to offer superior corrosion resistance. All joints are hand TIG welded using precise fixtures and tooling. We take great pride in knowing your new exhaust will sound remarkable and stand the test of time.

All piping is constructed of mandrel-bent T304L stainless steel to offer superior corrosion resistance. All joints are hand TIG welded using precise fixtures and tooling. We take great pride in knowing your new exhaust will sound remarkable and stand the test of time.

Engine movement and exhaust weight are transferred into the exhaust hangers, which puts a lot of stress on the mount brackets. IE's catback system is manufactured with multi-point and boxed-in hanger mounts designed to stand the test of time. Drive confidently knowing your exhaust is securely mounted and protected against annoying rattles or breaks.

Sections comprised of dual 2.5" piping running in parallel are reinforced and bridged to offer superior strength and weight dispersion. This minor detail works hard to reduce stress on the welds and protect the piping from vibrations and twisting that can lead to leaks and rattles.

Enjoy a tuned and enjoyable exhaust note without any raspy leaks ruining the show. Our exhaust system assembles with our wide-width stretch clamps designed to seal and pull your exhaust connections together. This style of clamp design is popular in high-end OE applications and is known for long-term reliability.

Vehicle Fitment:

  • 2017+ Audi S4 B9 3.0T

What clients say


  • Really fast and high quality customer support, my order got to me faster than the quoted time too. No complaints

  • The team took a mostly broken car after some work done elsewhere, and have systematically made it reliable and fast for a fair price. The staff are invested in the work they do which also makes a big difference.

  • Jeff was extremely helpful in assisting me with my exhaust. Always kept me updated and answered any queries in a timely manner. Will definitely be coming back for my future mods

  • Justin and his crew is amazing! Always ready to help and service with a smile. Trusty, friendly and reliable! Had my car sent in for repair twice and it’s fixed on time, at a reasonable price and with no issues. Highly recommended!

  • Easy to deal with and part was ordered quickly

Fitment & Compatibility


How do I know if this part fits my car?

We recommend checking your vehicle's make, model, year, and variant carefully. Most product listings include compatibility notes, but if you're unsure, contact us before purchasing.

Can you confirm fitment before I place my order?

Absolutely. Send us your VIN or Rego and we’ll confirm fitment for you.

Do you offer installation at your workshop?

Yes, we offer installations for most parts at our Ringwood workshop. Contact us to book or get a fitting quote.

Shipping & Handling


How long will it take for my order to arrive?

Most in-stock items ship within 1-2 business days. Delivery time depends on your location and shipping option chosen at checkout.

Do you ship internationally?

Currently, we only ship within Australia. For international enquiries, please contact us directly.

Can I pick up my order in person?

Yes, local pickup is available from our Ringwood workshop. Simply select ‘Local Pickup’ at checkout and we’ll notify you when your order is ready.

Please note: Some items are stored offsite and may need to be transferred from our warehouse, which can add a few business days before pickup is available.

Returns & Warranty


Can I return a product if it doesn’t fit?

Returns are accepted within 14 days if the item is unused and in original packaging. Please see our full Returns Policy for details.


What warranty comes with your products?

All products come with the manufacturer’s warranty. If you experience any issues, contact us and we’ll assist with the claim process.