Introduction: Unlocking the Full Potential of Your E63

Upgrading the turbochargers on your Mercedes-AMG E63 is one of the most impactful modifications you can make for substantial horsepower and torque gains. The factory turbochargers are capable, but the Pure Turbos Stage 2 Kit is engineered to deliver significantly higher flow, improved spool characteristics, and the durability needed for sustained high-performance driving. While a turbo replacement is a demanding job, it is a manageable project for an experienced DIY enthusiast with the right preparation and guidance. This detailed guide covers every phase of the process—from gathering the proper tools and safety equipment to post-installation tune considerations—ensuring you can complete the swap with confidence and enjoy a reliable, high-output E63.

Tools, Materials, and Workspace Preparation

A clean, organized workspace and a complete set of tools are essential for a smooth turbo replacement. Rushing or missing a critical tool mid-job leads to frustration and potential mistakes. Below is a comprehensive list of what you will need.

Essential Hand Tools

  • Socket set: Metric, deep and shallow, 3/8″ and 1/2″ drive (8mm through 19mm). Extensions of various lengths are critical for reaching tight fasteners.
  • Torque wrench: Two wrenches are ideal—a 3/8″ drive for lower torque values (10–50 ft-lb) and a 1/2″ drive for higher values (50–150 ft-lb). Calibrate or verify accuracy before use.
  • Wrench set: Combination wrenches (8–19mm) plus crow’s foot adapters for oil line fittings.
  • Screwdrivers: Flathead and Phillips in various sizes for clamp and electrical connector removal.
  • Pry bars and picks: For stubborn hose connections and seized bolts.
  • Breaker bar: 1/2″ drive, 18–24 inches long to break loose exhaust manifold bolts.
  • Torx and hex bits: T25, T30, T40, and hex sizes (6mm, 8mm) are common on Mercedes fasteners.

Specialty Items and Consumables

  • Pure Turbos Stage 2 Kit: Includes the new turbochargers, gaskets, and hardware. Verify the kit matches your specific E63 model year (M157 engine).
  • Engine oil and coolant: Use OEM-spec oil (e.g., 0W-40 or 5W-40 Mercedes MB 229.5) and genuine Mercedes coolant concentrate mixed 50/50 with distilled water. Have at least 8 quarts of oil and 2 gallons of premixed coolant on hand.
  • Shop towels and degreaser: For cleaning mating surfaces and managing fluid spills.
  • Penetrating oil: Apply to exhaust bolts a day before starting to ease removal.
  • Thread locker: Medium-strength (blue) for turbo bolts and bracket fasteners.
  • Anti-seize compound: For exhaust manifold studs and oxygen sensor threads.
  • New hardware: OEM turbo-to-manifold bolts, oil line crush washers, and exhaust flange springs/nuts. Do not reuse old fasteners.

Safety and Environment

  • Battery disconnect tools: A memory saver can retain radio and ECU settings, but disconnecting the battery is safest for electrical work.
  • Jack and jack stands: Use a low-profile floor jack and four quality jack stands rated for at least 3 tons each. Never work under a vehicle supported solely by a jack.
  • Wheel chocks: Place behind the rear wheels for stability.
  • Fire extinguisher: Rated for chemical and electrical fires.
  • Proper lighting: An LED work light or headlamp is invaluable in the engine bay.

Safety Precautions and Preliminary Steps

Before turning a single bolt, take these precautions to protect yourself and your vehicle.

  • Disconnect the battery: Remove the negative terminal and wait at least 15 minutes for the capacitors to discharge. This prevents accidental airbag deployment and ECU damage.
  • Allow the engine to cool completely: Exhaust components remain hot for hours. A cold engine also reduces the risk of burns and makes gasket removal easier.
  • Lift and secure the vehicle: Raise the front of the car high enough to access the underside. Place jack stands under the designated lift points (front subframe). Lower the car gently onto the stands and test stability.
  • Remove engine covers and under-trays: Take off the decorative engine cover and the plastic belly pan under the engine. This reveals the turbo area and drain points.
  • Drain engine oil and coolant: To prevent spills when disconnecting the turbo oil and coolant lines, partially drain the oil pan and radiator. Remove the oil drain plug and the radiator drain cock. Reinstall plugs after draining to avoid contamination.

Removing the Factory Turbochargers

Removal is the most labor-intensive phase. Work methodically, labeling bags of bolts and connectors as you go. The following steps assume both turbos are being replaced; if only one is faulty, Pure Turbos recommends replacing both for balanced airflow and performance.

Disconnect Intake and Exhaust Systems

  • Unfasten the intake air ducts from the air filter boxes to the turbo inlets. Loosen the hose clamps and carefully separate the rubber couplings.
  • Remove the intercooler pipes that run to the throttle body. On the M157, the intercooler is integrated into the intake manifold; you may need to remove the manifold for access. Detach the charge air cooler pump harness and hoses if necessary.
  • Unbolt the exhaust downpipes from the turbo outlets. The bolts are often difficult to reach; use a long extension and universal joint. Soak with penetrating oil first. Discard the old gaskets.
  • If your E63 has an air suspension, be cautious of the air lines and ride height sensors near the exhaust. Avoid pulling or kinking them.

Remove Oil and Coolant Lines

  • Oil feed lines: These are small-diameter lines from the engine block to the turbo. Use a crow’s foot wrench to avoid rounding the fittings. The line ends are banjo bolts with crush washers—replace the washers upon installation.
  • Oil drain lines: The larger lower return line can be stiff and difficult to maneuver. Unbolt the drain tube from the turbo and the block. Expect some residual oil to spill; have shop towels ready.
  • Coolant lines: Two lines connect to each turbo. Clamp the hoses to minimize coolant loss, then disconnect. Label which line goes to the supply and return ports.

Unbolt and Extract the Turbochargers

  • Support the turbo from below with a jack and a block of wood. The turbo is heavy; do not let it hang on the manifold bolts.
  • Remove the bolts securing the turbo to the exhaust manifold. On the M157, the manifold is part of the cylinder head (integrated). The studs can corrode; use a torque wrench to avoid snapping them. If a stud breaks, extraction is very difficult and may require removing the manifold—proceed with caution.
  • Once all bolts are out, gently wiggle the turbo free. Rotate it to clear the engine block and chassis rails. Lift it straight up and out of the engine bay. Repeat for the second turbo.
  • Inspect the manifold studs and clean the mounting face with a razor scraper. Ensure no old gasket material remains. Cover open ports with clean rags to prevent debris entry.

Preparing for Pure Turbos Stage 2 Installation

Before bolting in the new turbos, take time to familiarize yourself with the kit and perform critical checks.

  • Inspect the new turbos: Rotate the compressor wheels by hand—they should spin freely without binding. Look for any shipping damage, especially on the compressor housing fins or the wastegate actuator arm.
  • Prime the oil system: Pour a small amount of clean engine oil into the oil feed port on each turbo and rotate the wheel by hand to distribute it. This prevents dry start damage.
  • Check the wastegate actuator: The Stage 2 turbos come with an upgraded actuator. Ensure the rod moves smoothly and the spring tension is correct. If equipped with an electronic wastegate module, verify the connector orientation matches your vehicle’s harness.
  • Gather fresh fasteners: Use only the supplied bolts and gaskets. Apply a small amount of anti-seize to the exhaust manifold studs and blue thread locker to the turbo mounting bolts.

Installing the Pure Turbos Stage 2 Kit

Installation is the reverse of removal, but attention to detail is paramount for sealing and longevity.

Mount the Turbochargers

  • Place the new gasket on the manifold studs. Orient it correctly—the gasket is usually marked “out” or has a specific shape.
  • Lift the turbo into position. Use the jack and wood block again to support it while you align the studs. Do not force it; slight wiggling helps seat it.
  • Thread the mounting bolts by hand—never with an impact driver. Torque them to 25–30 ft-lb in a cross pattern if more than one bolt per turbo. Refer to the Pure Turbos instructions for exact torque values; they sometimes require a specific angle or sequence.

Reconnect Lines and Pipes

  • Oil feed and drain: Install new crush washers on the banjo bolts. Tighten to 18–22 ft-lb. For the drain line, use a new O-ring or gasket and torque to 10–12 ft-lb. Ensure the drain line has a gentle slope to prevent oil pooling.
  • Coolant lines: Reattach the hoses to the correct ports. Tighten the hose clamps securely. Top off coolant later.
  • Intake and exhaust: Reconnect the intake ducts and downpipes with new gaskets. Torque the downpipe bolts to 30–35 ft-lb. Double-check all clamps and bolts for tightness.
  • Electrical connectors: Plug in the wastegate actuator and any temperature sensors. Ensure harnesses are routed away from hot exhaust components and moving parts.

Post-Installation Procedures

The work continues after the wrenches are put away. These final steps are critical for the turbos’ longevity and performance.

Refill Fluids and Prime the System

  • Oil: Fill the engine with the recommended amount (check dipstick). Do NOT start the engine yet.
  • Coolant: Refill the cooling system with premixed coolant. Open the bleed valve on the heater hose (if equipped) to release trapped air. Fill until coolant appears at the bleed.
  • Prime the oil system: Disconnect the fuel pump relay or fuse to prevent the engine from starting. Crank the engine for 10–15 seconds in three or four intervals (with 30-second cool-downs between). Watch the oil pressure gauge—pressure should climb within seconds. This pre-lubes the turbo bearings before the engine fires.
  • Reconnect the fuel pump relay.

Start-up and Leak Check

  • Start the engine and let it idle. Immediately check for oil and coolant leaks around the turbo connections. A small drip may appear from a loose line—shut off and tighten if necessary.
  • Listen for any unusual noises: whining, grinding, or exhaust leaks. A slight whistle from the intake is normal; a scraping sound requires immediate shutdown.
  • Allow the engine to reach operating temperature. Monitor coolant temperature and oil pressure on the cluster. The auxiliary water pump may cycle on—this is normal.
  • After the engine has cooled, recheck all fluid levels and top off as needed. Inspect the turbo area for any signs of weeping or loose bolts.

ECU Adaptation and Road Testing

  • Turbo adaptation: Many E63s require an ECU reset or adaptation after turbo replacement. Use a compatible scan tool (e.g., Xentry, iCarsoft, or a high-end OBD scanner) to clear fault codes and teach the wastegate positions. Driving the car in a specific load cycle may be necessary—consult the tuning instructions.
  • Road test: Drive gently for the first 20–30 miles, avoiding full throttle. Gradually increase boost to allow the turbos and seals to break in. After 100 miles, perform a few full-throttle pulls in a safe area to verify performance and check for boost leaks.
  • Retorque bolts: After the first heat cycle, recheck the turbo mounting bolts, downpipe bolts, and oil line fittings. Retorque if needed.

Tuning and Performance Considerations

The Pure Turbos Stage 2 kit is designed for significant flow increases over the stock turbos. However, to fully realize its potential, additional modifications and tuning are necessary.

  • Engine management: The factory ECU cannot adjust boost and fuel delivery for larger turbos. A custom tune by a reputable Mercedes tuner (e.g., Eurocharged, Weistec, or Renntech) is mandatory. Expect gains of 80–130 whp and 100+ ft-lb over stock with proper calibration.
  • Fuel system: At Stage 2 power levels, the high-pressure fuel pump and injectors may be maxed out. Upgraded injectors and a low-pressure fuel pump are often recommended. Consult your tuner.
  • Intercooling: The factory intercooler system is marginal for sustained boost at Stage 2 levels. Upgrading to a larger heat exchanger or a secondary auxiliary pump helps maintain intake air temperatures. Pure Turbos offers a recommended intercooler upgrade kit.
  • Exhaust and intakes: Free-flowing downpipes and a high-flow intake system reduce backpressure and improve spool. Many owners pair the Stage 2 kit with a cat-back exhaust for a complete system.

For additional technical details and owner experiences, consult MBWorld’s E63 forum or the Pure Turbos support page for model-specific guidance. Always verify compatibility with your E63’s model year and existing modifications.

Common Pitfalls to Avoid

  • Snapping manifold studs: Use penetrating oil, heat if necessary, and never use an impact wrench on fasteners.
  • Oil leaks at banjo bolts: Always replace crush washers and torque to spec. Over-tightening distorts the washer and causes leaks.
  • Coolant air pockets: Improper bleeding leads to overheating. Use a vacuum filler tool if available, or run the engine with the coolant cap off and heater on full to burp the system.
  • Forgetting the wastegate link: If the wastegate actuator rod is not properly clocked, boost control will be erratic or the actuator will hit the chassis. Adjust the rod length per the instructions.
  • Skipping break-in: Aggressively boosting a brand-new turbo can damage the bearings. Follow the break-in period meticulously.

Conclusion: Performance Worth the Effort

Replacing your E63’s turbochargers with the Pure Turbos Stage 2 Kit is a demanding but deeply rewarding project. The time invested in careful removal, meticulous installation, and proper post-install procedures pays off with a dramatic increase in power, quicker spool, and a more responsive driving experience. By following this expanded guide—attending to every torque value, gasket orientation, and adaptation step—you ensure a reliable build that will deliver thrilling performance for many miles. Pair the turbos with a professional tune and supporting modifications, and your E63 will rival some of the fastest sedans on the road.