The Scion FR-S (and its nearly identical siblings, the Subaru BRZ and Toyota GT86) is a driver’s car by design: lightweight, rear-wheel drive, and balanced. Its naturally aspirated 2.0-liter FA20 boxer engine makes around 200 horsepower, which is plenty for nimble handling, but many enthusiasts crave more. An aftermarket turbocharger is one of the most effective ways to transform the FR-S into a genuine performance machine, adding 80 to 150 wheel horsepower depending on the kit and tuning. However, the installation is not a weekend project for the faint of heart. It requires careful planning, mechanical skill, and a solid understanding of forced induction. This article walks you through exactly what to expect when adding a turbocharger to your Scion FR-S, from choosing the right kit to long-term maintenance.

Understanding Turbocharging for the FA20 Engine

The FA20 is a high-compression (12.5:1) direct-injection boxer engine. It was never designed from the factory for forced induction, so adding a turbocharger involves more than just bolting on hardware. Unlike traditional turbocharged engines with lower compression ratios and stronger internals, the FA20 requires careful management of boost, fuel, and ignition timing to avoid detonation. Most aftermarket turbo kits for the FR-S include a thicker head gasket or recommend forged pistons for higher boost levels, but many owners successfully run low boost (5–8 psi) on the stock internals with a proper tune.

Key benefits of turbocharging the FA20 include:

  • Substantial horsepower gains – typical stage 1 kits yield 250–300 wheel horsepower, while built engines can exceed 400 hp.
  • Expanded torque curve – the naturally aspirated engine peaks near redline; a turbo fills the mid-range with usable torque.
  • Improved drivability – with a well-sized turbo and good tune, the car remains daily-drivable while offering dramatically more performance on demand.

However, the stock fuel system and ECU have limitations. Direct injection alone cannot supply enough fuel for high boost; many kits require port injection or upgraded injectors. The factory ECU also lacks built-in boost control and proper ignition compensation, so standalone or piggyback engine management is essential. Dedicated forums like FT86Club are excellent resources for real-world owner experiences.

Selecting the Right Turbo Kit

Not all turbo kits are created equal. The FR-S/BRZ aftermarket offers dozens of options, ranging from budget-friendly off-the-shelf kits to custom, race-oriented setups. The three most common categories are:

Entry-Level / Low-Boost Kits

These kits (e.g., the Greddy T517Z or Turbonetics TNX) typically include a small turbo, modest intercooler, and basic oil/coolant lines. They aim for 5–8 psi on stock internals. Prices range from $2,500 to $4,000. Installation is straightforward, but tuning is still mandatory.

Mid-Range / Street Kits

Examples include the HKS GTII Supercharger (though it’s a supercharger) or the BorgWarner EFR 6258-based kits. These produce 300–350 whp with upgraded fuel components. Expect to spend $4,500–$7,000 for the hardware plus a clutch upgrade.

High-Flow / Built Engine Kits

For those chasing 400+ whp, Full-Race and PTE (Precision Turbo Engine) kits use large turbos, massive intercoolers, and require forged pistons, rods, and fuel system overhauls. Costs easily exceed $10,000.

When choosing a kit, prioritize quality of the manifold (wastegate placement matters for boost control) and intercooler efficiency. Read kit-specific build threads on FT86Club’s forced induction section before buying.

Preparation and Tools

Before you even unbolt the first nut, gather everything needed. A turbo install on the FR-S can be done in a home garage, but it will take a full weekend at minimum—longer if you’re new to the platform. Essential items include:

  • Complete turbo kit (turbocharger, manifold, downpipe, intercooler, piping, oil/water lines, hardware).
  • ECU tuning solution (e.g., ECUTek, Haltech Elite 1500, or Delicious Tuning Flex Fuel kit).
  • Upgraded fuel pump (DW200 or AEM 340 LPH) if not included in the kit.
  • Boost gauge and wideband O2 sensor for monitoring.
  • Tools: socket set (10, 12, 14, 17, 19 mm), ratcheting wrenches, torque wrench, pry bar, jack stands, engine hoist (optional for engine removal if doing internals).
  • New gaskets for exhaust manifold and intake manifold.
  • Engine oil and coolant (high-quality synthetic 5W-30 and OEM Subaru coolant or equivalent).

Also consider a clutch upgrade. The stock clutch struggles with even 250 ft-lb of torque; after a turbo install it will quickly slip. An ACT Heavy Duty or Exedy Stage 1 clutch is recommended for street use.

Step-by-Step Installation Walkthrough

Below is a high-level overview. Always follow your specific kit’s instructions first. The general process for a turbo installation on a Scion FR-S is:

  1. Disconnect battery and drain coolant/oil. Remove the plastic underbelly tray.
  2. Remove the intake system (airbox, intake tube, manifold). Unbolt the factory exhaust manifold and front pipe. You’ll need to disconnect O2 sensors and wastegate.
  3. Install the turbo manifold onto the engine. Use new gaskets and torque bolts to spec (typically 25–30 ft-lb). Attach the turbocharger with its oil and water fittings.
  4. Run oil feed and return lines. The feed line is usually tapped from the passenger side of the engine block (near the oil pressure sensor). The drain line goes to the oil pan; you may need to weld or tap a bung. Some kits include a sandwich plate at the oil filter.
  5. Install the intercooler and charge pipes. The intercooler mount behind the front bumper. Secure piping with silicone couplers and T-bolt clamps. Ensure no rubbing against hoses or chassis.
  6. Reinstall intake manifold and connect vacuum lines for the blow-off valve and wastegate. Wire boost control solenoid if your ECU supports it.
  7. Install the downpipe and reconnect exhaust. Use a new gasket and oxygen sensor (A/F sensor) if required.
  8. Fill with oil and coolant. Prime the turbo by disconnecting the crank sensor or fuel pump relay and cranking the engine 15–20 seconds without starting to let oil circulate. Alternatively, pre-oil with a drill pump.
  9. Check for leaks before starting. Tighten all clamps, double-check oil connections. A small oil leak can destroy the turbo.
  10. Start the engine and listen for unusual noises. Let it idle, check for exhaust leaks, and verify that boost gauge reads near zero vacuum. Allow the engine to reach operating temperature while monitoring oil pressure and coolant temp.

If everything sounds normal, do a careful first drive. Stay out of boost for the first 50 miles to let the ECU adapt to the new fueling, then get to a tuner for a proper calibration.

Tuning and Engine Management

You cannot simply install a turbo and drive away without tuning. The FA20’s ECU uses a combination of direct injection and port injection (on some models) to maintain stoichiometric mixtures. A turbo imposes much larger air mass flows that the factory ECU cannot compensate for. The most common solutions are:

  • ECUTek reflash – a reprogrammed stock ECU with custom boost/fuel maps. Tuners like Delicious Tuning offer reliable off-the-shelf tunes for popular kits, but a dyno tune is recommended for safety.
  • Haltech elite 1500 or Link Fury – standalone ECUs that totally replace the factory unit. They give full control over spark, fuel, boost, knock detection, and allow flex fuel (E85) support. Standalones are preferred for high power but require professional wiring and tuning.

Never skip a tune. Running a turbo engine with stock calibration will cause detonation and likely destroy the pistons and rings within minutes.

Post-Installation Expectations

After a successful turbo install and tune, the driving experience is transformed. You’ll notice:

  • Strong mid-range pull – the torque dip between 3500–4500 rpm vanishes. Instead, the FA20 pulls hard from 3500 to redline.
  • Increased noise – the turbo whistle, blow-off valve, and louder exhaust become part of the character. Some find the cabin drone annoying; optional resonator installation can help.
  • Higher engine and oil temperatures – forced induction generates more heat. An oil cooler is highly recommended for track use. Monitor coolant temp gauge—if it rises during hard driving, consider a larger radiator.
  • Clutch slip – as mentioned, the stock clutch will likely give out within a few weeks if you drive hard. Budget for a clutch replacement.
  • Fuel economy decrease – when in boost, fuel consumption spikes. On the highway cruising far from boost, it can still return 25–28 mpg.

Potential Pitfalls and Common Mistakes

Even experienced mechanics encounter issues. Watch out for:

  • Oil feed restrictions – using too small an oil line will starve the turbo, causing premature bearing failure. Minimum 1/8″ NPT feed with a 0.065″ restrictor.
  • Exhaust leaks – a leak before the turbo reduces boost pressure and can cause exhaust gas temperature spikes. Use new gaskets and a torque wrench.
  • Improper intercooler piping – piping that contacts the radiator or chassis can rub through over time. Secure it with zip ties or bracket clamps.
  • Not re-torquing exhaust hardware – manifold bolts can loosen after heat cycling. Re-torque after 200 miles.
  • Ignoring fuel system limitations – stock injectors max out around 280 whp on the FR-S. If you exceed that, you need upgraded injectors and possibly a port-injection setup.

Additionally, if you live in a region that requires emissions testing, a turbo system often does not retain all OEM sensors and catalytic converters. Check local laws before proceeding.

Maintenance for a Turbocharged FR-S

Reliability depends on diligent maintenance after the build. Keep these practices:

  • Short oil change intervals – change to high-quality synthetic 5W-30 or 0W-40 every 3,000 miles or 6 months. Used oil analysis is cheap insurance.
  • Inspect oil return line – it clogs over time, causing seal failure. Check for kinks and clean if needed.
  • Monitor boost levels – a sudden drop could indicate a leak or stuck wastegate. A defective boost controller can cause overboost and engine damage.
  • Check intercooler couplers – every 5,000 miles, tighten all T-bolt clamps. They loosen with heat cycling.
  • Keep a logbook – record dyno pulls, oil temp, and any knock events (if using an ECU with knock logging). Share logs with your tuner.
  • Spare parts – carry a spare set of spark plugs (colder range for turbo) and a boost gauge in case of failure.

Conclusion

Installing an aftermarket turbocharger on your Scion FR-S is one of the most rewarding modifications you can make, delivering a dramatic leap in performance while preserving the car’s balanced character. However, it demands respect for the engineering involved. Proper preparation, a quality kit, meticulous installation, and a professional tune are non-negotiable for reliability. Whether you choose a low-boost street kit or a full race setup, the result is a car that pulls with authority and provides a genuine smile every time you row through the gears. With regular maintenance and attention, your turbocharged FR-S can serve as a thrilling daily driver or a track weapon for years to come.