The AWE Tuning BRZ Turbo Kit is one of the most respected forced-induction packages for the Subaru BRZ, Scion FR-S, and Toyota 86 twins. Designed to deliver strong, reliable power gains without sacrificing daily drivability, this kit can be tuned to produce up to 350 wheel horsepower when paired with the right supporting modifications and careful calibration. This guide walks through each critical component, the tuning process, and the best practices to hit that 350 hp target safely and consistently.

Understanding the AWE Tuning BRZ Turbo Kit

The AWE Tuning BRZ Turbo Kit is engineered specifically for the FA20 engine, balancing drive quality with high output. It includes a precision-machined turbocharger, cast exhaust manifold, front-mount intercooler, blow-off valve, and all necessary piping and hardware. The kit is designed to be a complete bolt-on system, but reaching 350 hp requires moving beyond the base configuration. Factory injectors and fuel pump become limiting at that power level, and the stock ECU calibration must be overwritten with a custom tune.

Key components of the standard kit include:

  • Garrett GTX2871R or similar high-efficiency turbocharger
  • Cast stainless steel exhaust manifold with heat shielding
  • High-flow front-mount intercooler core
  • Integrated blow-off valve
  • Aluminum charge piping with silicone couplers
  • Oil feed and drain line kit

Key Components for Maximum 350 HP Output

Achieving 350 wheel horsepower on the FA20 requires careful selection of every part that interacts with the turbo system. While the AWE kit provides an excellent foundation, these upgrades are necessary to deliver the airflow, fuel, and timing control that 350 hp demands.

High-Flow Turbocharger Selection

The included turbocharger in the AWE kit is capable of supporting 350 hp, but the exact model matters. The Garrett GTX2871R is a popular choice because it spools quickly and flows enough air for 350 whp on pump gas. If you're buying the kit new, specify the GTX2871R option. The key is to match the compressor map to your power target while keeping boost response tight. For 350 hp, target boost around 15–18 psi on 93 octane, with a turbine housing sized for early spool (0.64 A/R typically).

Upgraded Intercooler

The AWE front-mount intercooler is adequate for 300–320 hp, but heat soak can become an issue in sustained pulls or track driving at 350 hp. Consider upgrading to a core with a larger vertical cross-section and fin density designed for high-flow applications. A bar-and-plate core with cast end tanks reduces pressure drop and improves heat rejection. Lower intake air temperatures (IATs) directly translate into more consistent power and reduced risk of knock.

Performance Fuel Injectors and Fuel Pump

Stock BRZ fuel injectors (typically 440 cc/min) run out of capacity beyond 300 whp. To support 350 hp, you need injectors in the 550–700 cc/min range. Brands like Injector Dynamics, Bosch, or DW offer drop-in solutions. Coupled with a higher-flow in-tank fuel pump—such as a Walbro 525 or AEM 340 lph—the fuel system can deliver the extra volume required. The factory returnless fuel system can be retained if the pump is capable, but you may need a fuel pressure regulator to maintain stable pressure under high load.

ECU Calibration (Remapping)

Custom ECU tuning is non-negotiable for reaching 350 hp safely. The stock ECU logic can be overwritten using software like EcuTek or COBB Accessport. Key parameters that must be recalibrated:

  • Fuel tables: AFR targets for high load should be around 11.5–12.0:1 to keep exhaust gas temperatures safe.
  • Ignition timing: Retard timing under boost to prevent knock, while advancing at lower loads for fuel economy.
  • Boost control: Use a 3-port electronic boost controller or the internal wastegate solenoid with proper PID tuning to hit target boost without overshoot.
  • Load and torque limits: Increase the calculated torque limit to avoid premature throttle closure.

Additional Supporting Modifications for 350 HP

A turbocharger alone won't get you to 350 hp. The FA20 breathes through a restrictive intake and exhaust from the factory. These mods ensure the engine can efficiently ingest and expel the increased volume of air:

  • Cold-air intake: A high-flow intake (e.g., K&N, HKS, or Perrin) reduces restriction before the turbo. Make sure it includes a heat shield to keep IATs low.
  • Catless or high-flow front pipe and exhaust: Stock catalytic converters create backpressure that chokes high-flow turbos. A 3-inch catless or GESI-equipped downpipe with a 3-inch cat-back exhaust minimizes restriction.
  • Oil cooling: At 350 hp, oil temperatures can spike quickly. Add a thermostatically controlled oil cooler (Setrab or Earl's) to maintain oil temps below 230°F during hard use.
  • Transmission and clutch: The stock BRZ transmission and clutch may not hold 350 ft-lbs of torque reliably. Upgrade to a stage 2 clutch from ACT, Exedy, or OS Giken, and consider a fluid change to Motul for better heat resistance.

The Tuning Process Step by Step

Achieving a clean, safe 350 hp tune requires a systematic approach. Here is the recommended workflow:

  1. Mechanical installation: Install the AWE turbo kit, upgraded intercooler, injectors, fuel pump, intake, and exhaust per manufacturer instructions. Double-check all hose clamps, oil line routing, and wiring for the boost controller.
  2. Base flash: Load a base map from your tuner or tuning software that matches your component list. The base map should be conservative—around 280–300 hp on low boost.
  3. Initial startup and leak check: Start the engine and inspect for oil leaks, coolant leaks, and air leaks. Smoke test the intake system if possible.
  4. Street log and refine: Perform low-load street driving to trim fuel trims and check idle stability. Gradually introduce partial-throttle boost to ensure AFRs and timing are safe.
  5. Dyno tuning: On a chassis dynamometer, perform full-throttle pulls starting at 8–10 psi, increasing boost in 3-psi increments. Monitor knock (KNK), AFR, and fuel pressure. Target 11.5:1 AFR and zero knock retard.
  6. Final adjustment: Once boost is dialed to 15–18 psi (depending on your turbo and fuel), refine timing and boost control. Log multiple runs to verify consistency and check for heat soak.
  7. On-road verification: Test the tune in real-world conditions—highway merge, uphill pulls, and hot ambient temperatures. Ensure the car pulls smoothly without hesitation or knock.

Installation Tips for Maximum Performance

Proper installation prevents common pitfalls that limit power output or cause failures:

  • Always replace all gaskets and o-rings with fresh OEM or high-quality aftermarket equivalents. Copper or graphite exhaust gaskets resist blowout.
  • Torque all turbo and manifold bolts to spec (typically 35–40 ft-lbs for manifold-to-head studs). Use a torque wrench; don't guess.
  • Route the oil drain line with a gentle slope to avoid oil pooling in the turbo bearing housing. A -10 AN drain line is recommended.
  • Use a dedicated vacuum source for the blow-off valve to ensure proper response. Avoid tapping into the intake manifold that may cause idle instability.
  • Wrap the downpipe and exhaust manifold in titanium or DEI heat wrap to reduce under-hood temperatures. This helps IATs and protects nearby components.
  • After installation, double-check that all charge pipe couplers are seated fully and clamps are tightened. Loose clamps can cause boost leaks that limit power.

Final Tuning Adjustments and Safety Checks

After the initial dyno sessions, fine-tune these parameters to pull every last safe horsepower while preserving engine health:

  • Knock correction: If you see any knock retard (KR) above 1–2 degrees, pull 1 degree of timing from the affected load/rpm cells. Repeat until KR is under control.
  • Fuel trim adaptation: Allow the ECU to adapt short-term and long-term fuel trims. If LTFT exceeds ±5%, rescale the MAF calibration or adjust the injector flow rate.
  • Boost control duty cycle: Adjust the wastegate duty cycle to achieve target boost smoothly. Overly aggressive duty cycles can cause boost spikes. Use closed-loop boost control if your software supports it.
  • Throttle mapping: Some tuners flatten the torque request to reduce abrupt throttle response under boost. Personal preference; aim for linear pedal feel.
  • Cold start and warm-up: With larger injectors, you may need to re-tune the cranking and after-start fuel tables to avoid rich misfire or hard starting.

After final adjustments, perform a hot restart test: park the car and let it heat soak for 15 minutes, then restart and check for vapor lock, hard starting, or abnormal idle. If everything is clean, the car is ready for daily driving and occasional track use.

Dyno Results and Expected Power Curves

A well-tuned AWE BRZ Turbo Kit with the upgrades described typically produces the following numbers on a Dynojet chassis dynamometer:

  • Base kit (stock injectors, no fuel pump, 12 psi): 310–320 whp / 270–280 ft-lbs
  • With injectors, pump, intercooler, and 16 psi: 340–350 whp / 295–310 ft-lbs
  • With catless exhaust and optimized timing: 350–365 whp / 310–320 ft-lbs

Torque peaks around 4000–4500 rpm, with a flat curve holding strong to 7000 rpm. Power continues to climb to redline, making the FA20 feel alive and responsive in the mid-range and top-end.

Reliability Considerations for 350 HP

350 whp is well within the safe limits of the FA20 block and heads when properly tuned, but longevity depends on thermal management and maintenance. Follow these guidelines:

  • Change oil every 3000 miles using full synthetic 5W-30 or 5W-40 (Amsoil, Motul, or Red Line).
  • Monitor oil temperature. Install a gauge if your ECU dash doesn't display it. Keep it below 240°F.
  • Avoid aggressive throttle applications before the engine is fully warm (oil temps >160°F).
  • Consider an upgraded radiator (Koyo, CSF) and a high-flow thermostat if you track the car.
  • Respect the torque limits of the transmission. Hard launches with sticky tires can snap second gear.

External Resources

For further reading and tune examples, consult these authoritative sources:

Conclusion

Hitting 350 horsepower with the AWE Tuning BRZ Turbo Kit is a rewarding project that transforms the Subaru BRZ into a genuinely quick sports car. The process demands careful component matching, methodical tuning, and a focus on stability over outright peak numbers. When executed correctly, the result is a linear, responsive powerband that retains the character of the FA20 while delivering thrill-ride acceleration. By following the steps outlined in this guide—upgrading fuel delivery, optimizing airflow, and fine-tuning the ECU—you can confidently and reliably unlock the full potential of the AWE kit.