Introduction: Unlock the Full Potential of Your W205 C63

The Mercedes-AMG C63 (W205) is already a formidable machine, armed with a hand-built 4.0-liter twin-turbo V8 that produces intoxicating power. However, the factory exhaust system, while competent, is a compromise—designed to meet global noise regulations while minimizing weight and cost. Upgrading to an Akrapovic exhaust system is one of the most effective modifications you can make to this platform. Akrapovic, a Slovenian manufacturer renowned for its motorsport pedigree, offers exhaust systems crafted from high-grade titanium and carbon fiber that deliver significant weight savings, increased horsepower, and a symphony of sound that truly does justice to the M177 engine.

This guide provides a comprehensive, step-by-step approach to installing an Akrapovic exhaust on your W205 C63. Whether you are a seasoned DIY mechanic or an enthusiastic owner with basic tools, following this detailed walkthrough will ensure a proper installation that maximizes performance gains and delivers that spine-tingling exhaust note. Always prioritize safety, work methodically, and refer to the manufacturer’s instructions that come with your specific Akrapovic kit (catalytic converter-back, downpipe-back, or full system) as variations exist between sedan (W205) and coupe (C205) models.

Tools, Materials, and Workspace Preparation

Before you lift a finger, gather all necessary tools and parts. Rushing to find the right socket halfway through a job leads to frustration and mistakes. Having everything at hand streamlines the process and minimizes the time your car is on jack stands.

Category Item Notes
Required Tools Metric socket set (8mm–18mm), including deep sockets 1/2-inch drive for larger bolts; 3/8-inch for smaller fixings
Breaker bar (at least 18 inches) Essential for stubborn exhaust flange bolts
Torque wrench (20–150 ft-lb range) Calibrated; critical for final tightening
Jack and two heavy-duty jack stands (3-ton capacity) Hydraulic floor jack strongly recommended
Pry bar / flathead screwdriver For removing rubber exhaust hangers
Rubber mallet To tap stubborn exhaust joints loose
Penetrating oil (e.g., PB Blaster, WD-40 Specialist) Soak bolts 24 hours before if possible
Safety glasses, mechanic gloves, and hearing protection Exhaust work creates debris and noise
Consumables & Optional New exhaust gaskets (if not included) Often needed at downpipe-to-midpipe connection
Anti-seize compound (copper or nickel-based) Prevents future corrosion on bolts
Exhaust hanger lubricant (soapy water or silicone spray) Eases removal and installation of rubber mounts
Heat shield wrap (optional) Protects adjacent components; Akrapovic exhausts run hotter near catalytic converters
Digital caliper or alignment tool For precise tip positioning

Ensure your workspace is well-ventilated (especially if using penetrating oil) and that you have enough lighting to see under the vehicle. If you have access to a lift, that is ideal; otherwise, jacking up the rear—and preferably the front as well—will give you better access to the entire exhaust system.

Vehicle Preparation and Safety

  1. Park on level ground and engage the parking brake. Chock the front wheels.
  2. Allow the exhaust to cool completely. Even after a short drive, temperatures can exceed 500°F (260°C). Work on a cold system to avoid burns and to make removal easier (heat cycles expand and contract metal).
  3. Disconnect the battery negative terminal (12mm bolt) to prevent any electrical shorts from the exhaust valve solenoid (if your Akrapovic system includes electronic valve control). Wait five minutes before proceeding.
  4. Jack up the vehicle: Position the hydraulic jack under the rear differential (the most central point) and raise the car. Place jack stands under the designated lift points on the rear subframe—never under the exhaust or suspension arms. Lower the car onto the stands and test for stability.
  5. For better access, you may also jack up the front and support on stands, but a rear-only lift is sufficient for a cat-back install.

Removing the Factory Exhaust System

The stock W205 C63 exhaust is one piece from the downpipes to the rear muffler. It is heavy and awkward—ideally you will have a helper to lower it safely.

Step 1: Loosen the Flange Bolts at the Downpipes

Working from the rear, locate the two flanges connecting the exhaust to the primary catalytic converters (downpipes). These are almost directly under the front seats. Use a 13mm socket and breaker bar to loosen the four bolts. They are often tight from corrosion; apply penetrating oil and let it sit for 10 minutes if necessary. Do not remove them completely yet—just break them loose.

Step 2: Remove the Rubber Hangers

Under the car, you will see several rubber isolator hangers supporting the exhaust along the transmission tunnel and rear axle. Using a pry bar or your hands with lubricant, gently pull the metal exhaust studs out of the rubber mounts. Start at the frontmost hanger and work your way back. The rear muffler hangers are the most challenging—spray silicone lubricant into the rubber eyelets to ease removal.

Pro tip: If a hanger is too tight, use a pair of pliers to compress the rubber and twist the exhaust stud. Avoid cutting the rubber unless absolutely necessary—you will reuse them.

Step 3: Disconnect the Rear Muffler Connections (if applicable)

On some W205 models, the rear muffler has additional connections to the midpipe via V-band clamps. If your stock system has these, loosen them with a 13mm wrench or socket. The Akrapovic system typically replaces everything from the downpipe back, so you will be removing the entire rear section anyway.

Step 4: Lower the Exhaust

With all hangers released and flange bolts removed (but still holding the weight), have a helper support the exhaust near the rear muffler. The stock system weighs approximately 35–40 lbs (16–18 kg). Carefully slide the exhaust forward slightly to clear the downpipe flanges, then lower it to the ground. Be mindful of the oxygen sensor wiring—if your car has post-cat sensors, they may be attached to the stock midpipe. Unplug them by pressing the tab and pulling the connector apart.

Important: Inspect the downpipe flanges for corrosion, gasket residue, and flatness. Clean them with a wire brush and a rag. The stock gaskets are usually single-use—plan to replace them with new ones (often supplied in the Akrapovic kit).

Installing the Akrapovic Exhaust

Akrapovic systems are renowned for their precision fitment. However, because the W205 C63 has both sedan (W205) and coupe (C205) configurations with slight differences in underbody layout, verify your kit’s compatibility. The installation order is generally: midpipe(s) → rear muffler(s) → adjust tips.

Step 1: Pre-Assembly and Dry Fit

Lay out all Akrapovic components on a clean surface. Compare them to the stock system. Note the orientation of the hangers—Akrapovic uses its own hanger brackets that mount to the factory rubber isolators. Also check the carbon fiber exhaust tips (if equipped) for orientation and scratch protection. Do not install the tips yet.

Step 2: Install the Midpipe Section

Slide the midpipe (or two middle sections) into place, connecting to the downpipe flanges. Use the supplied gaskets (or new OEM gaskets) and hand-tighten the bolts. Do not fully torque them yet—leave slight movement for alignment. Attach the midpipe to the transmission tunnel hangers using the Akrapovic-supplied brackets and reuse the rubber isolator mounts.

Step 3: Attach the Rear Muffler

With the help of a second person, position the rear muffler (or two mufflers in the case of the C63 S with electronic valves) onto the midpipe. Connect the slip joints or V-band clamps—finger-tight only. Attach the muffler to the rear hanger brackets. The Akrapovic system typically uses a single central mounting point or two side brackets; follow the kit instructions.

Step 4: Connect Exhaust Valve Actuators (if applicable)

If your Akrapovic system includes electronic exhaust valves (to control sound via the factory AMG drive selector modes), plug in the solenoid connectors. Ensure the wires are routed away from heat sources and sharp edges, securing them with zip ties provided in the kit. Test valve operation by pressing the exhaust button in the car (or cycling through drive modes) before finalizing the install—this will save you major frustration later.

Step 5: Align and Torque All Connections

With all sections loosely connected, align the system from front to back. Check that the exhaust runs parallel to the underbody and does not contact the rear sway bar, heat shields, or differential. This is the time to adjust hanger length or slide joints.

Torque specifications (typical—always verify in your kit manual):

  • Downpipe flange bolts: 16 ft-lb (22 Nm) for M8 bolts
  • V-band clamps: 35 ft-lb (48 Nm)
  • Hanger bracket bolts: 8 ft-lb (11 Nm)

Use a torque wrench on all critical fasteners. Over-tightening titanium bolts can cause galling; apply anti-seize if specified.

Step 6: Install the Carbon Fiber or Titanium Tips

The final cosmetic touch—install the exhaust tips. Akrapovic typically uses spring-loaded clamps that allow you to adjust tip depth and angle. Center the tips in the rear bumper cutouts. Measure from the bumper edge to ensure both sides are equal. Once satisfied, torque the clamp screws to the specified value (often 4 ft-lb / 5.5 Nm).

Post-Installation Checks and Testing

A careful inspection before starting the engine can prevent exhaust leaks, rattles, or even damage from misalignment.

Visual and Clearance Inspection

  • Rotate the steering wheel lock-to-lock to verify the front exhaust sections do not contact steering components or the front anti-roll bar.
  • Check that the exhaust is at least 1/2 inch away from any heat shields, wiring, fuel lines, or brake lines.
  • Re-install any underbody panels you removed (Akrapovic often requires trimming of the factory panel—use the template provided).

Leak and Sound Test

  1. Reconnect the battery negative terminal.
  2. Start the engine and let it idle. The exhaust will be louder than stock, but listen for any hissing or popping sounds from the joints—these indicate a leak. A quick method: with a cold exhaust, spray soapy water on each joint; bubbles reveal leaks.
  3. If no leaks are audible, rev the engine gently to 2,000–3,000 RPM while the system warms up. Listen for rattles from the hangers or heat shields. Tighten any loose connections.
  4. Let the engine cool to ambient temperature, then re-torque all fasteners once more after the first heat cycle (metal expands and settles).

Road Test

Take a short test drive on varied roads: low-speed cruising, moderate acceleration, and a WOT (wide-open throttle) pull in a safe area. Listen for drone at highway speeds (Akrapovic titanium systems are designed to minimize drone, but some frequency changes are normal). Check for any check engine light (which could indicate an O2 sensor issue if you removed sensors or if the system changes backpressure). Most cat-back Akrapovic systems do not require a tune, but if you also changed downpipes, a tune is recommended.

Performance and Sound: What to Expect

The Akrapovic exhaust is not just about noise. It delivers tangible performance improvements.

Aspect Stock Exhaust Akrapovic Exhaust
Weight (cat-back system) ~38 lbs (steel) ~22 lbs (titanium/carbon)
Power gain (claimed) Baseline +7–10 hp, +10–13 lb-ft (on a cat-back)
Sound character Refined, muted, some turbo whistle Deep, raw, aggressive with clear V8 burble
Weight reduction — Significant weight off the rear axle, improving rotational inertia and response

Owners commonly report a much more linear throttle response and a willingness to rev—partly due to reduced backpressure and partly to the lower weight of the titanium construction. The sound is unmistakably exotic, with a deep bellow under load and a unique crackle on overrun. If you have the Akrapovic system with valves, you retain the ability to quiet the exhaust in comfort mode, making it daily-driver-friendly.

Maintenance Tips for Your Akrapovic Exhaust

Titanium exhausts require specific care to maintain their appearance and functionality.

  • Cleaning: Use a mild soap and water solution, or dedicated titanium cleaner (avoid acidic wheel cleaners). The blue/purple heat tint that develops at the tips is normal and cosmetic—some owners love it, others polish it off.
  • Bolts and clamps: Re-torque all fasteners after the first 100 miles and then annually. Titanium fasteners can loosen if not checked.
  • Rubber hangers: Inspect for cracks every 12 months; replace if worn. The vibration characteristics of a lighter exhaust can stress hangers differently.
  • Winter driving: If you drive in salted roads, consider an anti-corrosion coating (though titanium is highly resistant to corrosion—watch for electrolysis between dissimilar metals).

Conclusion

Installing an Akrapovic exhaust on your W205 C63 is a transformative upgrade. It sheds significant unsprung weight, liberates a few extra horsepower, and most importantly, unleashes the full acoustic glory of the AMG V8. By following this detailed guide—taking your time with removal, aligning the system carefully, and performing thorough post-installation checks—you will achieve a professional-level result that will reward you every time you press the start button.

For further reading, consult the official Akrapovic installation manual for your specific W205 C63 system on the Akrapovic website. Community forums like MBWorld offer invaluable real-world experiences. And for precise torque specifications on your Mercedes, refer to the workshop manual or a trusted source such as STAR TekInfo.

Disclaimer: Working on a vehicle’s exhaust system involves high temperatures, heavy components, and jack stands. Always use safety equipment. If you are not confident in performing this installation, please consult a certified Akrapovic installer or a reputable Mercedes-Benz specialist.