A Deep Dive into the BMW M2 Competition and the Aerocharger Turbo Upgrade

The BMW M2 Competition, particularly the F87 generation (2018–2021), is already a celebrated driver’s machine. Its S55 twin-turbo inline-six, a detuned version of the engine found in the M3 and M4, delivers 405 hp and 406 lb-ft of torque straight from the factory. For many, that’s more than enough. But for the enthusiast who tracks their car regularly or simply craves a broader power band, a bolt-on turbocharger upgrade can transform the car into a genuine supercar slayer. One of the most compelling options in the aftermarket is the Aerocharger variable-geometry turbocharger, which claims a gain of 150 wheel horsepower for an investment of around $4,200.

This article explores everything you need to know about this specific upgrade: how it works, what it costs (including hidden expenses), installation demands, tuning requirements, and how it stacks up against other popular power adders like hybrid turbos, larger single-turbo conversions, or a simple tune-and-downpipe package.

What Makes the Aerocharger Different?

Traditional fixed-geometry turbochargers rely on a wastegate to regulate boost pressure. This design can create a tradeoff between spool speed and top-end flow. The Aerocharger uses a variable-geometry turbine (VGT) system, which adjusts the angle of the vanes in the turbine housing to optimize exhaust gas velocity. At low RPM, the vanes close slightly, increasing backpressure to accelerate spool. At high RPM, they open fully to reduce restriction and maximize power.

This is the same core technology found in many diesel engines and in the Porsche 911 Turbo, but Aerocharger has packaged it as a direct bolt-on upgrade for the S55 platform. The result is a turbocharger that can deliver boost much earlier than a similarly sized fixed-geometry unit, while still supporting substantial peak horsepower numbers.

Key Technical Specifications

  • Compressor wheel: Billet aluminum, high-flow design (specific inducer/exducer dimensions vary by kit version)
  • Turbine housing: Integrated VGT actuator (electronic vacuum-controlled)
  • Wastegate: Internal (integrated into the VGT mechanism)
  • Boost range: Typically 22–28 psi (dependent on tune and fuel)
  • Power claim: +150 whp over stock (approx. 550–570 whp with supporting mods on 93 octane)
  • Installation: Direct bolt-on to stock S55 manifolds and intake piping (requires removal of factory turbos)

The Aerocharger is not a "larger turbo" in the traditional sense. It is designed to maintain the spool characteristics of the small, quick-spooling stock turbos while pushing more air volume at the top end. That is the key differentiator: you gain high-RPM power without sacrificing low-RPM throttle response, which is often the Achilles' heel of larger single-turbo conversions on the S55.

Breaking Down the $4,200 Price Tag

The initial $4,200 figure typically covers the complete Aerocharger turbocharger assembly, including the VGT actuator and necessary hardware. However, a realistic budget for the full upgrade must account for additional items:

  • Aerocharger kit: ~$4,200
  • ECU tuning: $800–$1,500 (custom tuning or off-the-shelf software from brands like BootMod3, MHD, or EcuTek)
  • Supporting modifications: High-flow intake ($300–$600), upgraded charge cooler or heat exchanger ($500–$1,000), larger intercooler ($500–$800), colder spark plugs ($80–$100)
  • Labor: 8–12 hours at a competent shop = $800–$1,800
  • Fuel system upgrades: Optional but recommended for E85 blends – port injection or HPFP upgrade ($1,500–$3,000)

The all-in cost for a well-executed 150+ whp gain is more realistically in the $6,000–$9,000 range. The $4,200 turbo itself is only one piece of the puzzle. That said, compared to a full single-turbo kit (which can cost $6,000–$10,000 before installation and tuning), the Aerocharger remains competitively priced.

Cost Comparison with Other Power Upgrades

Upgrade PathTypical CostMax Safe WHP (93 octane)
Stage 2 tune + downpipes + intercooler$2,000–$3,500~500 whp
Hybrid turbos (e.g., Pure Stage 2+)$4,500–$6,000 (parts only)~580 whp
Single-turbo kit (e.g., Pure, Doc Race)$7,000–$12,000~700+ whp
Aerocharger VGT$4,200 + supporting mods~550–580 whp

Note: The above table assumes a safe tune on pump gas. With E85 or methanol injection, the Aerocharger can push beyond 600 whp, but that requires a more comprehensive fuel system.

Installation and Tuning Considerations

Installing the Aerocharger is a direct bolt-on job for the S55 engine. That means you remove the factory twin-scroll turbos and replace them with the single Aerocharger unit using the existing manifold flanges and plumbing. The physical swap is straightforward for an experienced DIYer or a BMW specialist shop, but there are two critical points to address:

  • Oil and coolant lines: The Aerocharger uses the same feed and return locations as the factory turbos, but you must ensure proper routing to avoid kinks.
  • VGT actuator integration: The vacuum-driven actuator needs a control signal. Most tuners will use a separate boost controller or incorporate control into the ECU via a custom calibration.

ECU Tuning Is Mandatory

You cannot simply bolt on the Aerocharger and run the stock tune. The airflow characteristics are completely different. You will need a custom tune or a well-developed off-the-shelf map from a tuner familiar with the Aerocharger. Popular options include:

  • BootMod3 – OBDII flash tuning with excellent community support. Several custom tuners offer Aerocharger-specific maps.
  • MHD Flasher – Another reliable platform, often paired with custom tuners like Kies Motorsports or Pro Tuning Freaks.
  • Custom dyno tuning – Always the safest bet if you have a local shop with a Mustang or Dynojet. The VGT vanes can be tuned across the RPM range for optimal spool and top-end power.

A word of caution: the Aerocharger's VGT system can create very high exhaust manifold pressure if the vanes are not properly calibrated. This can lead to heat soak, boost spikes, or even engine damage. Invest in a reputable tune and monitor boost and EGTs carefully during initial testing.

Performance Gains: More Than Just Peak Numbers

The headline 150 whp increase is impressive, but the real story is the area under the curve. With the Aerocharger, the S55 can reach 20 psi by 2,800 RPM—significantly earlier than a typical hybrid turbo setup. That means you get usable torque well below 3,000 RPM, making the car feel responsive in daily driving while still pulling hard to redline.

In real-world terms, a well-tuned M2 Competition with the Aerocharger and supporting mods (intercooler, intake, downpipes) can achieve:

  • 0–60 mph: 3.3–3.5 seconds (stock is ~4.0)
  • Quarter-mile: 11.3–11.6 seconds at 122–126 mph
  • 60–130 mph: 8.0–8.5 seconds (stock is ~11.0)

These numbers put the car in the same league as the Dodge Challenger Hellcat or a Porsche 911 Turbo (996/997 generation), but with far less weight and better handling. Track enthusiasts will also appreciate the sustained boost pressure in third, fourth, and fifth gears—there is no drop-off at high RPM as you often see with stock turbos.

Reliability and Longevity Concerns

The Aerocharger VGT technology has been used in the off-road and diesel markets for years, but it is relatively new to the BMW S55 community. Some early adopters reported issues with the vacuum actuator diaphragm failing after a few thousand miles, causing the vanes to stick. Aerocharger has since released an improved actuator assembly, and most tuners now recommend periodic inspection of the vacuum lines.

On the positive side, the Aerocharger's oil-cooled center housing reduces the risk of coolant seal failures common to some water-cooled hybrids. The billet compressor wheel is also more durable than cast wheels when spinning at high RPM. If you keep the tune conservative (around 550 whp) and use quality oil with proper warm-up procedures, the turbo should last as long as a factory unit—typically 80,000–100,000 miles before needing a rebuild.

What About the Engine Internals?

The S55 has forged rods and pistons from the factory, so 550–580 whp is well within the engine's safe operating range. Many tuned S55s run 600–650 whp on the stock bottom end without issues. The main weak points at that power level are the crank hub, which can spin under high load, and the PCV system, which can push oil into the intake under higher boost. Upgrading the crank hub (e.g., with a pinned or pressed-on solution) is strongly recommended if you plan to track the car or use drag radials.

Competing Upgrades: How Does It Compare?

To place the Aerocharger in context, here is how it stacks up against the two most common S55 turbo upgrades:

Hybrid Turbos (e.g., Pure Stage 2+, Vargas GC, Mosselman)

  • Pros: Proven reliability, many tuners, moderate cost, retain twin-scroll response.
  • Cons: Still have some turbo lag compared to the VGT Aerocharger; peak power often requires higher boost and more aggressive tuning.
  • Price: Comparable to Aerocharger ($4,000–$5,500).

Single Turbo Conversion

  • Pros: Massive top-end power (700+ whp), simpler engine bay, single wastegate.
  • Cons: Significant lag, expensive ($7,000+), requires custom intake and downpipe plumbing, often loses low-end torque.
  • Best for: Racing on tracks with long straights or drag strip use.

The Aerocharger hits a sweet spot: it offers hybrid-like spool but with a broader power band and higher peak capacity than most hybrid options. It is not the cheapest, nor the most powerful, but it is arguably the best "all-around" turbo upgrade for the M2 Competition that retains daily drivability.

Final Verdict: Is the Aerocharger Worth It?

The BMW M2 Competition is already a brilliant driver's car. The Aerocharger VGT turbo takes everything that makes the S55 engine special—its immediate response, linear power delivery, and refined character—and amplifies it. For the enthusiast who wants a significant, measurable improvement in lap times and straight-line performance without the compromise of lag or drone, this upgrade delivers.

The $4,200 price for the turbo itself is competitive, but the true cost of a reliable installation (including tuning and supporting mods) will be closer to $7,000–$9,000. That is still less than many single-turbo kits and cheaper than a supercharger conversion. If you value responsiveness and a seamless power delivery above all else, the Aerocharger is one of the best investments you can make for your M2 Competition.

For further reading, check out Aerocharger's official product page for the S55: Aerocharger S55 VGT Turbo. You can also find owner experiences and dyno charts on the F87 Owner's Forum and detailed installation guides from Turner Motorsport.

Note: Always consult with a qualified BMW technician or tuner before purchasing any power-upgrade components. Every vehicle and driving scenario is unique, and proper tuning and installation are critical to reliability and safety.