Upgrading to the Cobb Tuning BRZ Turbo Kit: Power Gains and Performance Tips

The Subaru BRZ has earned its reputation as a driver’s car, praised for its low curb weight, perfectly balanced chassis, and engaging rear-wheel-drive dynamics. Yet for many enthusiasts, the stock 200-horsepower naturally aspirated boxer engine leaves room for desire. The Cobb Tuning BRZ Turbo Kit is one of the most complete and well-engineered forced induction solutions on the market, designed to transform your BRZ without sacrificing the reliability that makes it a daily-driver favorite. This article provides an in-depth look at the power gains you can expect, the installation process, critical tuning considerations, and performance tips to get the most out of your turbocharged Subaru.

What’s Included in the Cobb Tuning BRZ Turbo Kit

The Cobb Tuning BRZ Turbo Kit is a comprehensive forced induction package engineered for the FA20 engine found in the Subaru BRZ (and its twins, the Scion FR-S and Toyota 86). Unlike piecemeal turbo kits that require sourcing separate components, Cobb delivers everything needed in one box, with a focus on quality, fitment, and drivability.

Core components of the kit include:

  • Garrett GTX2860R Gen II turbocharger – a proven, ball-bearing turbo that spools quickly and supports high flow rates without excessive lag.
  • Air-to-air intercooler – reduces intake air temperatures to prevent knock and maintain consistent power.
  • Cobb cast turbo manifold – engineered for optimal flow and durability under high heat.
  • Downpipe and intake piping – mandrel-bent stainless steel for smooth airflow.
  • Blow-off valve – recirculating design maintains driveability and reduces turbo surge.
  • All necessary hardware, gaskets, and hoses – the kit is designed for a “no-drill” installation on stock engine bays.
  • Accessport V3 hand-held tuner – pre-loaded with Cobb’s off-the-shelf OTS maps for immediate drivability.

Because the kit is engineered as a unit, clearance issues and mismatched components are virtually eliminated. This makes it a strong choice for both experienced builders and first-time turbo installers.

Power Gains: What to Expect on Your BRZ

The numbers speak for themselves. On a stock BRZ engine with the Cobb kit properly tuned, users commonly see:

  • Horsepower: increase of 70–110 whp (wheel horsepower) over stock, bringing total output to roughly 270–320 whp depending on fuel and tune.
  • Torque: increase of 80–100 lb-ft at the wheels, with a broad, flat torque curve starting as low as 3,000 rpm.
  • 0–60 mph times: drop from the stock ~6.2 seconds to the mid-4-second range with proper traction.
  • Quarter-mile: high-12-second passes are achievable, compared to the stock mid-14-second times.

These gains are measured on pump gas (93 octane or 91 octane with conservative timing). With E85 fuel and a custom tune, some owners report exceeding 350 whp on the stock block – though engine longevity at those levels requires additional supporting modifications.

It’s important to note that the FA20 engine has known limitations – particularly with the connecting rods and ring lands when pushing beyond 350 whp. The Cobb kit is designed to offer reliable power within safe limits, making it an excellent middle ground for enthusiasts who want a dramatic performance upgrade without building the bottom end.

Real-World Dyno Results

For context, a stock 2013 BRZ typically dynos at around 160–170 whp (drivetrain loss accounts for the difference from the 200 hp crank rating). After installing the Cobb turbo kit with the included OTS Stage 2 map (93 octane), the same car often records 260–270 whp on a Dynojet – a 100+ whp increase. On E85, figures climb above 300 whp. These gains are accompanied by a dramatic improvement in throttle response, with peak torque arriving nearly 2,000 rpm earlier than the naturally aspirated engine.

Before You Buy: Pre-Installation Considerations

Jumping into a turbocharger installation without proper preparation can lead to headaches or worse – engine damage. Before opening the kit, address these points.

Engine Health Check

Your BRZ’s engine should be in excellent mechanical condition. Perform a compression and leak-down test. Low compression on any cylinder can be a sign of worn rings or valve seat issues, which will be amplified under boost. Cobb recommends a fresh set of spark plugs (one step colder is ideal) and clean fuel injectors.

Fuel System Upgrades

The stock BRZ fuel system can support up to about 300 whp on 93 octane. Beyond that, consider upgrading to high-flow fuel injectors (e.g., 700cc or larger) and a higher-flow in-tank fuel pump. For E85, these upgrades are mandatory – the stock pump cannot deliver the volume required for flex fuel tuning.

Clutch Considerations

The factory clutch in the BRZ is designed for 200 hp. With 270+ whp, it will slip under hard acceleration. Plan for a stage 2 or stage 3 clutch kit – brands like ACT, Exedy, and Competition Clutch offer excellent options that handle the increased torque without an obnoxiously heavy pedal feel.

Cooling System Improvements

Forced induction raises under-hood temperatures. While the Cobb kit includes an intercooler, an upgraded radiator (e.g., Koyo, CSF) and a high-flow thermostat help manage coolant temps during extended pulls or track use. Oil cooling is also wise – consider an oil cooler or a larger capacity oil pan.

Installation Process: Step-by-Step Overview

Installing the Cobb Tuning BRZ Turbo Kit is a job that most DIY mechanics can complete over a weekend, provided they have moderate experience with turbochargers and proper tools. Below is a high-level overview. Always refer to the official Cobb installation instructions for torque specs and details.

1. Disconnect Battery & Drain Fluids

Start with a cold engine. Disconnect the negative battery terminal. Drain the engine oil and coolant – you’ll be removing the oil pan and water lines. Remove the factory intake system, including the air box and intake tube.

2. Remove Exhaust Components

Unbolt the factory exhaust manifold (header), catalytic converter, and front pipe. The turbo downpipe will replace the catalytic converter section. If you’re in a region with emissions testing, note that the kit removes the primary catalytic converter – you may need a high-flow catted downpipe as an alternative.

3. Install Turbo Manifold and Oil/Coolant Lines

Mount the Cobb turbo manifold to the cylinder heads. Attach the oil feed line to the turbo and connect it to an oil pressure source (typically a sandwich plate on the oil filter housing). The coolant lines require tapping the engine block or using pre-existing ports – the kit includes all necessary adapters.

4. Mount the Turbocharger and Intercooler

Bolt the Garret GTX2860R to the manifold. Install the intercooler in the front bumper area – the kit’s piping is designed to use the stock crash beam with minor trimming. Connect the intake piping, charge pipes, and blow-off valve.

5. Reassemble Exhaust and Intake

Install the downpipe (supplied), then reattach the mid-pipe and rear exhaust section. If you still have a stock catback exhaust, it will work but a 3-inch catback is recommended to reduce backpressure. Reinstall the intake snorkel and the MAF sensor in its new location.

6. Final Checks and Leak Testing

Double-check all clamps, oil lines, coolant connections, and wiring. Fill the engine with fresh oil and coolant. Pressure test the intake system for leaks using a boost leak tester. This is critical – a small leak can cause lean conditions and detonation.

Post-Installation Tuning: The Key to Reliability

The Cobb Accessport V3 that comes with the kit contains several off-the-shelf (OTS) maps designed to get you on the road quickly. However, for maximum performance and safety, a professional dyno tune or an e-tune from a Cobb-certified tuner is highly recommended.

Why a Custom Tune Matters

  • Fuel quality varies: OTS maps are conservative to accommodate poor fuel. A custom tune extracts more power from good 93 octane or E85.
  • Individual engine differences: Compression, injector flow rates, and altitude all affect optimal air-fuel ratios.
  • Safety margins: A tuner can dial in boost levels, ignition timing, and wastegate duty cycles to avoid knock while maximizing torque.

Many owners report a 15–30 whp gain going from the OTS Stage 2 map to a custom tune on the same fuel. Additionally, a tune can smooth out transient throttle response, making the car more enjoyable to drive daily.

Monitoring with the Accessport

After tuning, use the Accessport to monitor key parameters: boost pressure, intake air temperature, knock correction, engine oil temperature, and fuel pressure. Set up gauges on the display for real-time feedback. If you see persistent knock correction (negative values) under load, reduce boost or adjust the tune immediately.

Performance Tips for Your Turbocharged BRZ

Now that your BRZ is making serious power, a few supporting modifications and driving adjustments will help you stay out of the ditch and keep the powertrain healthy.

1. Upgrading the Cooling System

As mentioned earlier, a turbocharger generates significant heat. Beyond the intercooler, consider installing:

  • Oil cooler: helps maintain consistent oil temps during aggressive street driving or track sessions.
  • Coolant reroute or additional radiator: the stock cooling system is adequate for 300 whp on the street, but for track duty a larger radiator (e.g., Koyo 52mm) is wise.
  • Heat management tape or ceramic coating: wrapping the turbo manifold and downpipe reduces under-hood temperatures and helps the intercooler work more efficiently.

2. Suspension and Brakes

With 70–100% more power, your BRZ’s handling balance changes. Stock springs and dampers may feel overwhelmed under hard acceleration or braking. Consider:

  • Adjustable coilovers (e.g., Öhlins, KW, BC Racing) to lower the center of gravity and improve grip.
  • Upgraded brake pads and rotors – stock brakes fade quickly with repeated high-speed stops. A set of performance pads (Carbotech, Hawk) and slotted rotors will dramatically improve stopping power.
  • Quality tires: all-season or low-grip tires will spin through first and second gear. Summer performance tires (Michelin Pilot Sport 4S, Bridgestone Potenza RE-71RS) provide the grip needed to lay down power.

3. Drivetrain Reinforcements

The stock transmission and differential can handle 300 whp, but the clutch will not. Upgrade to a stage 2 organic clutch that holds 350+ lb-ft of torque while remaining daily-driver friendly. A short shifter and differential bushings can also improve shift feel and reduce drivetrain slop.

4. Regular Maintenance Intervals

Forced induction engines need more frequent fluid changes. Adopt the following schedule:

  • Oil change: every 3,000–4,000 miles using full synthetic 5W-30 or 0W-40 (check your tuner’s recommendation).
  • Spark plugs: inspect and gap every 20,000 miles; replace with one-step-colder plugs (e.g., NGK LFR7AIX) if extensively tracking the car.
  • Intercooler cleaning: inspect the core for debris every year to maintain heat rejection.
  • Belt and pulley inspection: the added load can stress accessory belts – replace at the first sign of cracking.

Potential Pitfalls and How to Avoid Them

While the Cobb kit is reliable, no turbo system is bulletproof. Here are common issues and preventive measures.

Boost Leaks

Loose silicone couplers or small splits in the charge pipes can cause a loss of boost pressure and lean conditions. After any service, perform a boost leak test using a pressure tester from Cobb Tuning or a generic PVC tester. Tighten all T-bolt clamps to spec (typically 45–50 in-lb on 2.5-inch couplers).

Oil Starvation

The FA20 engine uses a semi-dry sump oil system, but under high lateral G-forces and with an added oil drain line from the turbo, oil can momentarily slosh away from the pickup. An oil pan baffle or a larger capacity pan (e.g., IAG Performance) helps prevent oil starvation during track use. Always monitor oil pressure via the Accessport.

Fuel Pump Failure

Stock fuel pumps can fail prematurely when run near maximum duty cycle. If you are chasing E85 or high-boost numbers, replace the pump with a DeatschWerks DW300c or similar drop-in unit. Keep the pump sock clean to avoid clogging.

Overboosting

If the wastegate actuator fails or the control solenoid malfunctions, boost can spike above 12 PSI (the kit’s safe limit). After installation, verify that boost pressure matches the target map. A manual boost controller can be added as a failsafe, but Cobb’s electronic boost control solenoid is typically sufficient with proper tuning.

Comparing the Cobb Kit to Other Options

The BRZ turbo market includes offerings from Full Race, HKS, GReddy, and Jackson Racing (supercharger). The Cobb kit stands out for its complete, street-friendly package, pre-loaded Accessport maps, and the proven Garret GTX2860R turbo. Unlike centrifugal superchargers, the Cobb turbo provides linear, boost-by-gear power that feels OEM+ when cruising but pulls hard above 3,500 rpm.

For those who want the absolute maximum power on a stock block (350+ whp), a custom turbo kit with a larger GT3076R may be better, but requires more fabrication and a built engine to avoid failure. The Cobb kit occupies the sweet spot of reliable, daily-drivable forced induction with minimal compromises.

Final Thoughts

Upgrading to the Cobb Tuning BRZ Turbo Kit is one of the most satisfying performance modifications you can make to your Subaru BRZ. The gains are substantial – over 100 whp on pump gas – while the car retains excellent manners and drivability. By following proper installation procedures, investing in a professional custom tune, and adding supporting modifications like a stronger clutch and improved cooling, you can enjoy a truly transformed driving experience that rivals modern sports coupes costing twice as much.

Whether you’re chasing canyon roads, an autocross course, or simply wanting a quicker daily driver, the Cobb turbo kit delivers while keeping reliability at the forefront. For more detailed installation guides and community experiences, visit resources like FT86Club forums and Cobb Tuning’s official support page.