How to Make Your B9 S4 or S5 Faster Instantly: Hi-Flo and Catless Downpipes Explained

Want Your Audi To Sound Like This?

If you drive an Audi B9 S4 or S5, you already know the thrill of German engineering paired with turbocharged precision. But what if you could make that performance even sharper—boosting power, improving exhaust flow, and unleashing a deeper, more aggressive tone?

That’s where Fiber Imprints’ Hi-Flo and Catless Downpipes come in.

What Are Downpipes—and Why Do They Matter?

Your Audi’s downpipe is the first section of exhaust piping connected directly to the turbocharger. It’s responsible for channeling exhaust gases away from the turbo and through the rest of the exhaust system.

The factory downpipe, while efficient enough for stock performance, is also restrictive. It’s designed to meet strict emissions and noise regulations—not to maximize power. This restriction limits airflow and turbo efficiency, leaving untapped performance potential on the table.

Upgrading your downpipe means freeing your turbo to spool faster, breathe better, and deliver a noticeable increase in both horsepower and torque.

Hi-Flo Downpipe: Balance Power and Compliance

Our Hi-Flo Downpipe is designed for the enthusiast who wants improved performance without compromising daily drivability or emissions compliance (where applicable).

✅ Key Benefits:

  1. Optimized exhaust flow with a high-efficiency catalytic converter
  2. Faster turbo response and reduced turbo lag
  3. Enhanced exhaust note—deeper, throatier, but still refined
  4. Direct bolt-on fitment for the B9 S4 and S5 (no cutting or welding required)

Perfect for those who want street-legal performance gains while maintaining a balance of power and precision.

Catless Downpipe: Maximum Flow, Maximum Sound

For those chasing the purest performance possible, our Catless Downpipe delivers unrestricted exhaust flow for track use and off-road builds.

✅ Key Benefits:

  1. No catalytic restriction = maximum power and torque
  2. Sharper throttle response and quicker turbo spool
  3. Aggressive exhaust tone that turns heads
  4. Precision-crafted from premium materials for durability under extreme conditions

If you’re building a track weapon or tuned daily, this is the go-to choice for extracting every ounce of potential from your Audi’s turbocharged engine.

Precision Engineering Meets Premium Quality

At Fiber Imprints, we’re passionate about crafting components that blend performance, aesthetics, and reliability. Each downpipe is engineered for perfect fitment on the Audi B9 S4 and S5, utilizing:

  1. High-grade stainless steel or titanium construction for long-lasting durability
  2. CNC flanges for airtight sealing
  3. TIG-welded joints for unmatched strength
  4. Designed and tested for seamless integration with both stock and aftermarket exhaust setups

Every product is built to perform—and built to last.

The Sound of Performance

Nothing transforms your driving experience quite like the sound of a freer-flowing exhaust. With our downpipes, you’ll experience:

  1. A deeper, more resonant tone at idle
  2. Crisper, more aggressive pops on throttle and decel
  3. A distinct performance character that makes your Audi stand out

Pair it with a Fiber Imprints exhaust system for the ultimate sound and performance combo.

Why Choose Fiber Imprints?

✔ Designed by enthusiasts, for enthusiasts
✔ Exact fitment guaranteed for the B9 S4 and S5
✔ Fast, secure shipping across North America
✔ Top-tier materials and craftsmanship—no compromises
✔ Customer-first support before and after your purchase

We don’t just sell performance parts—we engineer confidence behind every upgrade.

Ready to Transform Your Drive?

Don’t let your Audi’s potential go untapped.
Experience the difference that Fiber Imprints Hi-Flo and Catless Downpipes make.

👉 Shop Now at FiberImprints.com
Elevate your sound. Enhance your performance.
Unleash your Audi.

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