Introduction

Upgrading your Subaru BRZ with a Garrett GTX2860R turbocharger is one of the most rewarding performance modifications you can undertake. The BRZ’s naturally aspirated FA20 engine is responsive and balanced, but forced induction unlocks substantial horsepower and torque gains—typically 280–320 whp on a conservative tune, with the potential for more when paired with supporting modifications. The GTX2860R is a proven choice for this platform, offering quick spool, excellent efficiency, and a broad powerband that retains daily-driver civility.

This guide provides a detailed, step-by-step walkthrough of the entire installation process. While the work is demanding and requires intermediate to advanced mechanical skills, following these instructions carefully will help you avoid common pitfalls and achieve a safe, reliable result. Before starting, understand that ECU tuning is mandatory—running a turbo without proper fuel and timing control can destroy your engine. Plan accordingly, and consider enlisting a professional tuner if you are not experienced with engine mapping.

Tools and Materials Needed

Assembling the correct tools and components before you begin prevents frustrating work stoppages. Beyond the core turbo kit, you will need a comprehensive set of hand tools, specialized items, and consumables.

Garrett GTX2860R Turbo Kit Components

  • Garrett GTX2860R turbocharger (typically 0.64 A/R turbine housing for quick spool)
  • Turbo exhaust manifold (often a tubular equal-length design specific to the BRZ/FR-S)
  • Intercooler core and charge piping kit (front-mount intercooler recommended)
  • Blow-off valve (BOV) or bypass valve
  • Wastegate (external, usually included with the manifold)
  • Oil feed and drain line kit
  • Coolant feed and return line kit
  • Downpipe (catless or high-flow catted)
  • Gasket set (manifold-to-head, turbo-to-manifold, downpipe-to-turbo, intake-to-turbo)
  • Hardware (studs, nuts, bolts, washers, lock washers)

Hand Tools and Shop Equipment

  • Socket set (metric: 8, 10, 12, 14, 17, 19 mm) with extensions and swivels
  • Combination wrenches (same sizes)
  • Torque wrench (1/2" drive for critical fasteners)
  • Screwdrivers (flathead and Phillips)
  • Pliers (standard, needle-nose, and hose clamp)
  • Jack and jack stands (four stands for level support)
  • Drain pan (for coolant and engine oil)
  • Breaker bar (for seized nuts)
  • Gasket scraper or razor blade

Additional Items and Consumables

  • Engine coolant (Subaru Super Long Life Blue or equivalent)
  • Engine oil (high-quality synthetic, 5W-30 or recommended weight)
  • Thread locker (blue Loctite) and anti-seize compound
  • Vacuum hose (silicone, 4 mm and 6 mm) and T-fittings
  • Boost gauge (mechanical or electronic, with sender)
  • ECU tuning solution (EcuTek cable and license, COBB Accessport, or open-source options)
  • Turbo blanket or heatshield (optional, but recommended for heat management)
  • RTV silicone gasket maker for oil drain flange

Preparation Steps

Workspace and Safety

Park your Subaru BRZ on a level, well-ventilated surface. Disconnect the battery negative terminal to prevent accidental shorts or electrical surges. Raise the vehicle using a jack and support it securely on jack stands at all four lift points. Never rely solely on a jack when working under the car. Allow the engine to cool completely—exhaust components can remain dangerously hot for hours after shutdown.

Fluid Draining

Drain the engine coolant by opening the radiator petcock and removing the reservoir cap. Also drain the engine oil; this is a good opportunity to perform an oil change with the correct grade for turbo charging. Remove the oil filter and set aside. The oil drain line from the turbo will connect to the oil pan, which is accessed most easily with the pan empty and removed later.

Preliminary Clearance Check

Before disassembly, test-fit the turbo on the manifold to confirm the orientation of the oil and coolant ports. Some BRZ-specific kits may require clearance modifications to the AC line or the alternator bracket. Addressing these issues now saves frustration later.

Removing the Stock Components

The BRZ’s engine bay is relatively compact, but thoughtful disassembly provides access to all necessary areas. Work slowly and label every connector and vacuum line.

Intake and Engine Cover Removal

  • Remove the engine cosmetic cover by prying off the two rubber grommets and lifting.
  • Disconnect the mass airflow (MAF) sensor electrical connector.
  • Loosen the clamps on the intake tube and remove the entire air intake assembly (filter box, snorkel, and ducting).
  • Disconnect the secondary air injection hoses if present (2013–2016 models).

Stock Exhaust Manifold and Heat Shielding

  • Unbolt the two heat shields covering the stock exhaust manifold. Some bolts may be rusted—apply penetrating oil.
  • Remove the oxygen sensors (both upstream and downstream) using a 22 mm oxygen sensor socket. Be careful not to damage the threads.
  • Unbolt the stock exhaust manifold from the cylinder heads (nine nuts and studs on the FA20). The manifold is heavy; support it while removing the final nuts.
  • Lower the manifold and discard it unless you plan to retain any bracketry.

Additional Disassembly for Access

  • Remove the starter motor (two bolts) to gain clearance for the turbo oil drain line routing on the driver's side.
  • Unbolt the alternator (move it aside without disconnecting wires if possible; otherwise disconnect and remove).
  • Remove the air conditioning compressor bracket bolts if they interfere with the new manifold—some kits require it.
  • Disconnect the coolant hoses from the throttle body and water pump area as needed for intercooler pipe routing.

Installing the Garrett GTX2860R Turbo

Turbo Manifold Installation

Clean the cylinder head gasket surfaces with a scraper and lint-free rag. Install the new manifold gaskets and place the turbo manifold against the heads. Hand-start all nuts and studs finger-tight, then torque to the manufacturer's specification (typically 32–38 lb-ft in a crisscross pattern). Use anti-seize on threads. Attach any included support brackets to the block.

Mounting the Turbocharger

Install the turbo-to-manifold gasket and mount the GTX2860R onto the manifold’s T3 flange. Use the supplied locking nuts and torque to 30–35 lb-ft. Verify the turbo compressor housing is oriented correctly for the charge piping (outlet facing forward or downward depending on kit). Install the wastegate actuator preloaded per Garrett instructions if included; otherwise, mount the external wastegate to the manifold runner.

Oil and Coolant Lines

Connect the oil feed line from the engine block (usually via a sandwich plate or a port under the alternator) to the turbo center housing. Use new copper or aluminum sealing washers. For the oil drain, drill and tap the oil pan (if not pre-tapped) or use a pre-fabricated drain adapter. Attach the drain line with a -10 AN fitting and secure with RTV at the pan flange. Run coolant lines from the water pump or crossover tube—ensure no kinks. A turbo blanket wrapped now before piping simplifies later access.

Intercooler and Charge Piping

Mount the front-mount intercooler (FMIC) behind the front bumper. Remove the crash beam reinforcement if necessary (many kits provide a shorter beam). Route the cold-side piping from the compressor outlet, through the intercooler, to the throttle body. The hot-side piping goes from the turbo outlet to the intercooler inlet. Use silicone couplers and T-bolt clamps at every joint. Install the blow-off valve on the cold-side pipe near the throttle body (recirculating or VTA as per tune requirements).

Connecting the Exhaust System

Downpipe Installation

Attach the downpipe to the turbo outlet turbine housing using a new gasket and four nuts (torque to 30 lb-ft). The downpipe must clear the steering shaft and the transmission bellhousing. If a flex section is included, ensure it is not under tension. Reinstall the oxygen sensors: the upstream sensor in the turbo exhaust housing or downpipe bung, the downstream sensor in the mid-pipe.

Reconnect the Exhaust

Connect the downpipe to the rest of the exhaust system (cat-back option pipe or stock muffler). Use a new gasket and tighten all clamps. Reinstall any heat shields that fit over the downpipe area—omitting them risks heat damage to nearby components and increased underhood temperatures. If you installed a catless downpipe, you will need a defouler or a tune that disables the rear O2 readiness check.

Final Assembly and ECU Tuning

Reconnecting Systems

  • Reinstall the alternator, starter, and AC bracket if removed. Torque to spec.
  • Reconnect all coolant hoses, refill with Subaru Blue coolant, and bleed the system (run engine with radiator cap off, heater on full, until air purged).
  • Fill the engine with fresh oil (do not pre-oil the turbo—it will receive oil on startup).
  • Install the boost gauge sender and run vacuum line to the intake manifold.
  • Reconnect the battery and check all electrical connectors.

Pre-Start Checks

Before cranking, verify all oil and coolant lines are tight, no wiring is caught in moving parts, and the intake tract is free of debris. Disconnect the fuel pump fuse or disable the coil packs and crank the engine for 10 seconds to prime the oil system. Reconnect everything and start the engine. Let it idle for 1–2 minutes, checking for leaks at every gasket, fitting, and hose. Shut off and confirm the oil level and coolant level are correct.

ECU Tuning

Without proper calibration, the GTX2860R will cause the engine to run dangerously lean under boost. Use an EcuTek ProECU kit or a COBB Accessport with a custom tune from a reputable tuner. At a minimum, you must adjust fuel injector scaling, ignition timing maps, and boost control. Many tuners EcuTek provide base maps that you can refine on a dyno or street log. If you are unfamiliar with tuning, book a remote session with a specialist platform like FT86 Speedfactory or a local Subaru performance shop.

Break-In and Verification

Drive gently for the first 100 miles, avoiding full boost. During this period, re-check all fasteners for tightness, watch for smoke from the downpipe (oil or coolant burn-off is normal short-term). Log fueling, knock correction, and boost pressure using your tuning software. After the break-in, perform a full-throttle pull in third gear while logging to ensure safe air/fuel ratios (target 11.5–12.0:1 under boost on gasoline).

Conclusion

Installing a Garrett GTX2860R turbocharger on your Subaru BRZ is a substantial project that delivers a transformative increase in power—ranging from 280 to over 350 horsepower at the wheels depending on boost level and supporting mods. This guide outlines every critical step, from disassembly and turbo mounting to piping and ECU calibration. By taking your time, using quality tools, and respecting the importance of tuning, you can achieve a reliable, streetable build that will reward you every time the wastegate opens. If any step feels beyond your comfort level, consult a professional installer or a community resource like the FT86 Club forums for guidance. The result is worth the effort.