Why the Audi RS5 Demands a Premium Cold Air Intake

The Audi RS5, powered by the formidable 2.9-liter twin-turbo V6 (EA839), is already a performance benchmark in its class. Factory engineering prioritizes a balance of power, emissions compliance, and noise reduction. The stock air intake system, while functional, introduces restrictions—tortuous air paths, small intake snorkels, and dense paper filters—that starve the turbos of cool, dense air. Replacing this with a purpose-built aftermarket cold air intake (CAI) is one of the highest-ROI modifications you can make. By reducing intake restriction and lowering intake air temperatures (IATs), a well-designed CAI can free up 15 to 20 wheel horsepower (whp) on a stock RS5, often with gains climbing higher when paired with an engine tune.

This guide examines the two leading cold air intake systems for the B9 and B9.5 Audi RS5: AWE Tuning and Cobb Tuning. We’ll cover how each delivers its gains, what separates them in design and sound, installation considerations, and whether the horsepower claims hold up in real-world dyno testing. Whether you’re chasing track-day tenths or simply want a more responsive daily driver, these intakes represent the best the market offers.

How Cold Air Intakes Unlock Horsepower in the RS5

Turbocharged engines like the RS5’s 2.9T are particularly sensitive to intake air density. A cold air intake works by reducing the temperature and turbulence of the air entering the engine’s compressor wheels. Cooler air contains more oxygen molecules per unit volume. With more oxygen available, the engine management system (ECU) can add more fuel, resulting in a more powerful combustion event. The factory intake system draws air from inside the engine bay through a convoluted path with resonators designed to mute induction noise. Aftermarket systems instead seal a large, low-restriction filter behind a heat shield or route it into the front bumper’s airflow, pulling air from outside the hot engine bay.

The primary measurable gains come from:

  • Reduced Intake Restriction: Factory airboxes typically flow around 650–700 CFM. Premium aftermarket intakes such as AWE or Cobb flow 750–850+ CFM, reducing the workload on the turbos.
  • Lower Intake Air Temperatures (IATs): Stock intakes can see IATs rise 30–50°F above ambient after repeated pulls. A heat-shielded cold air intake holds IATs within 10–15°F of ambient during sustained driving.
  • Quicker Turbo Spool: Less restriction means the turbos see less backpressure before the compressor wheel, improving spool time and throttle response.

It’s worth noting that while 15+ hp is advertised, dyno results vary. Most owner-verified dyno charts show net gains of 12–18 whp on a completely stock RS5 without tuning. When combined with a stage 1 ECU tune, these intakes often support 20–25 whp gains over a factory airbox.

Top Cold Air Intakes for the Audi RS5 Head-to-Head

Below we compare the two most installed options: AWE Tuning’s fully enclosed system and Cobb Tuning’s open-element design. Both offer dyno-verified gains, but their engineering philosophies differ significantly.

AWE Tuning Cold Air Intake Kit

AWE (Advanced World Engineering) has long been the gold standard for Audi performance parts. Their RS5 cold air intake is a two-piece system that replaces the entire stock airbox and intake ductwork.

  • Power Gains: 15–18 hp and 12–15 lb-ft torque at the wheels (independent dyno testing with 93 octane).
  • Design: Fully enclosed polycarbonate airbox with a clear lid. The housing seals against the hood to form a complete thermal barrier. The snorkel is enlarged and direct-mounts into the factory front grille inlet.
  • Filter: Dry, high-flow synthetic filter by AEM (no oil required). Washable and reusable.
  • Sound: Noticeably louder turbo spool and diverter valve noises without being obtrusive. No drone at cruising speed.
  • Installation: Straightforward removal of the factory box and reusing OEM mounting points. Requires about 45–60 minutes for an intermediate DIY user.
  • Warranty/Support: AWE backs the kit with their industry-leading customer service and a limited lifetime warranty.

Pros: Best-in-class heat rejection; proven power curve; retains factory oil catch can routing; visually stunning underhood.

Cons: Premium price (approx. $600–$700); clear lid may scratch over time if frequently cleaned.

Cobb Tuning Cold Air Intake Kit

Cobb Tuning is legendary in the Subaru and BMW tuning world, and they’ve brought the same engineering rigor to their Audi RS5 intake.

  • Power Gains: 14–16 hp and 10–13 lb-ft torque at the wheels.
  • Design: Large open-element cotton gauze filter (oil-based) behind a three-sided aluminum heat shield. The top of the filter remains exposed to the engine bay, depending on hood insulation for the seal.
  • Filter: Cobb-branded high-flow conical filter with pleated cotton gauze. Requires periodic cleaning and re-oiling.
  • Sound: More aggressive than AWE. Intake roar, louder turbo whistle, and sharp whoosh during gear changes.
  • Installation: Slightly easier than AWE—no lid to align. Typically 30–45 minutes.
  • Warranty/Support: Cobb provides a limited lifetime warranty and excellent technical support.

Pros: Lower price point (approx. $450–$550); easier filter access; great for those who want maximum induction noise; compatible with Cobb’s Accessport tune platform.

Cons: Open-element design allows more heat soak during extended idling; filter oil must be applied carefully to avoid MAF sensor contamination; less thermal protection than a full enclosure.

Other Notable Options

While AWE and Cobb dominate the aftermarket, two other intakes deserve mention:

  • Eventuri: Known for carbon-fiber enclosures and proprietary filter technology. Gains are slightly lower (12–14 hp), but the construction and sound quality are unparalleled. Price is $900+, limiting its audience.
  • Unitronic: Closed system similar to AWE but with a dry filter. Gains are on par with AWE (15 hp). Unitronic’s intake is more budget-friendly at ~$550 and pairs seamlessly with their software.

Installation Guide: What to Expect

Installing a cold air intake on a B9/B9.5 RS5 is a moderate difficulty project. You don’t need a lift, but you’ll need patience and basic tools: flathead screwdriver, T25 Torx bit, 10mm socket, pliers for hose clamps.

Step-by-Step Overview

  1. Disconnect the battery (ground terminal) to avoid any ECU fault codes or accidental MAF sensor damage.
  2. Remove the factory intake box by unclipping the two spring clips and disconnecting the crankcase ventilation hose (push-button connector).
  3. Unbolt the lower bracket holding the airbox to the chassis (10mm bolt). Carefully lift the entire stock assembly out.
  4. Disconnect the MAF sensor from the old intake tube. Pay attention to its orientation—it must be re-installed in the same direction.
  5. Install the lower heat shield (or AWE’s baseplate) using the factory mounting holes. Torque to spec.
  6. Attach the MAF sensor to the new intake tube using the supplied hardware. Ensure the sealing O-ring is well seated.
  7. Slide the main intake tube onto the turbo inlet. Tighten the T-bolt clamp firmly (8–10 Nm).
  8. Position the filter inside the heat shield. For AWE, snap on the clear lid. For Cobb, secure the filter and ensure the heat shield seals against the hood.
  9. Reconnect the crankcase vent hose to the new intake tube. Some kits require a small adapter.
  10. Double-check all clamps and connectors. No loose hoses or unsealed joints.
  11. Reconnect the battery. Start the engine and inspect for any codes using an OBD-II scanner (or Cobb Accessport if available).

Tip: If you’re installing an oiled filter like Cobb’s, give the filter time to dry thoroughly after cleaning—excess oil can foul the MAF sensor, causing lean-run conditions.

Real-World Dyno Results and Data

Independent dyno tests on a 2018 Audi RS5 (B9) with 93-octane fuel show the following averages:

  • Stock baseline: 404 whp / 428 lb-ft (Dynojet).
  • AWE Tuning intake only: 420 whp / 442 lb-ft – a gain of 16 whp and 14 lb-ft.
  • Cobb Tuning intake only: 418 whp / 440 lb-ft – a gain of 14 whp and 12 lb-ft.
  • With a stage 1 tune + intake (both): 460–470 whp / 480–500 lb-ft.

The AWE system’s closed design gives it a slight edge under continuous load (e.g., repeated 3rd-gear pulls), as heat soak from the engine bay is better controlled. The Cobb intake may initially produce higher peak gains on the first dyno run due to cooler-start conditions, but on a third or fourth consecutive pull, the open design shows IATs rising faster, resulting in a 3–5 whp drop versus the AWE closed box.

These numbers confirm that both intakes easily deliver the advertized 15+ hp increase, with AWE providing more consistent power in hot or aggressive driving conditions.

Maintenance and Long-Term Considerations

Cold air intakes require more maintenance than a stock paper filter. Here’s what you need to know:

  • Dry filters (AWE/AEM): Clean every 30,000 miles with a vacuum or compressed air (from the inside out). No oil needed. Expected life: 100,000 miles+ with proper care.
  • Oiled filters (Cobb): Clean and re-oil every 15,000–20,000 miles. Use Cobb’s cleaning kit (or K&N cleaner). Over-oiling can contaminate the MAF sensor—use the oil sparingly and let the filter sit for 30 minutes before installation.
  • Heat shield sealing: Over time, foam or rubber gaskets may compress. Inspect annually and replace if gaps appear.
  • MAF sensor cleaning: If you experience rough idle or hesitation, clean the MAF with CRC MAF cleaner (never touch the wires). This is especially relevant for oiled filter users.

Because the RS5’s turbochargers generate high heat, ensure the intake path is completely sealed after any maintenance. A small air leak downstream of the MAF can cause unmetered air entering the engine, leading to lean conditions and potential engine damage.

Choosing the Right Intake for Your Driving Style

Both AWE and Cobb are excellent choices, but your decision should hinge on your priorities:

  • Track or canyon driving: Choose AWE for superior IAT management and consistent power. The enclosed box keeps heat out, especially during back-to-back high-load corners.
  • Show quality and underhood aesthetics: AWE’s clear lid and billet aluminium couplers are beautiful. Cobb’s red logo and brushed aluminum tube also look good, but the open element is less visually impressive.
  • Maximum induction sound: Cobb wins here. The open design amplifies turbo spool and blow-off sounds significantly. If you want your RS5 to sound more aggressive, go Cobb.
  • Budget: Cobb is $150–$200 cheaper. If you’re planning to tune the car later, that extra money can go toward an Accessport or custom tune.
  • Ease of filter cleaning: Cobb’s oiled filter is faster to access (no lid to remove). AWE’s dry filter requires removing the clear lid, which adds a minute or two.

Installation Tools and Pro Tips

Before starting, lay out these tools:

  • T25 Torx driver – for hose clamps and small brackets.
  • 10mm socket and ratchet – for lower airbox bolt.
  • Flathead screwdriver – for prying spring clips.
  • Trim removal tool – helpful for disconnecting plastic hose fittings.
  • Torque wrench (small inch-pound) – for MAF sensor screws (20 in-lb recommended).

Pro tip: When installing the MAF sensor, apply a tiny bead of silicone dielectric grease to the sensor’s O-ring (non-conductive). This prevents moisture ingress and ensures a proper seal against vacuum leaks. Also, after installation, zero out the throttle adaptation by turning the ignition on (engine off), pressing the accelerator to the floor for 10 seconds, then releasing and turning off. This helps the ECU learn the new airflow characteristics.

Conclusion: Which Cold Air Intake Should You Buy?

Upgrading to a cold air intake is one of the most satisfying modifications you can make to your Audi RS5. Both AWE Tuning and Cobb Tuning deliver on their promises—real, measurable horsepower gains, sharper throttle response, and a thrilling intake soundtrack. The AWE system edges ahead in thermal management and consistency, making it the best overall choice for performance-driven owners who want no compromises. The Cobb system offers incredible value and sound for those who appreciate a more raw driving experience and can accept slightly higher IATs during prolonged hard driving.

If you’re planning a full stage 1 or stage 2 tune, both intakes pair perfectly with software from Unitronic, 034Motorsport, or APR. Remember to always verify your local emissions laws—some aftermarket intakes may not be CARB-legal in California. For most RS5 owners, the combination of improved power, sound, and reliability makes either intake a worthy investment. Unlock your engine’s potential today.

External resources: For detailed dyno charts and owner reviews, check AWE Tuning RS5 Intake Product Page and Cobb Tuning RS5 Intake Product Page. For installation walkthroughs, see this Audizine forum thread with independent dyno testing.