Installing a supercharger kit on your Scion FR-S (or its close relatives, the Subaru BRZ and Toyota GT86) is one of the most effective ways to unlock the car’s true potential. The FA20 engine responds exceptionally well to forced induction, transforming the already delightful chassis into a seriously quick machine. This guide provides a comprehensive, step-by-step walkthrough of the installation process, covers the tools and tuning required, and gives you realistic performance expectations based on common centrifugal and roots-style supercharger kits.

Pre‑Installation Considerations

Choosing the Right Supercharger Kit

Not all supercharger kits are created equal. For the Scion FR‑S, the two most popular designs are centrifugal superchargers (like the Vortech V3 or Jackson Racing C‑38) and twin‑screw positive‑displacement units (such as the Edelbrock E‑Force or Harrop HTV1320). Centrifugal kits tend to deliver linear power build‑up that peaks high in the rev range, while positive‑displacement blowers offer instant, low‑end torque. Your choice should align with your driving style and intended use—track, daily, or weekend toy.

Required Tools and Parts

Be thorough. Attempting a supercharger install with an incomplete tool set leads to frustration and potential damage. Here’s what you’ll need:

  • Complete supercharger kit – ensure it includes brackets, belt, pulleys, intercooler (if applicable), injectors, and fuel pump upgrade (if required)
  • Basic hand tools – metric sockets (8mm, 10mm, 12mm, 14mm, 17mm), combination wrenches, Allen keys, screwdrivers, pliers, and a pick set
  • Torque wrench – a ¼‑in drive for small bolts and a ⅜‑in or ½‑in drive for larger fasteners
  • Jack and jack stands – a level working surface is mandatory
  • Coolant drain pan and funnel – you’ll likely disturb the cooling system
  • Dyno tuning software or ECU flashing tool – e.g., ECUTek or OpenFlash Tablet
  • Safety gear – safety glasses, mechanic’s gloves, and a fire extinguisher within reach

Vehicle Preparation

Begin by parking on a level concrete floor. Disconnect the negative battery terminal and wait at least five minutes for the ECU capacitors to discharge. Note: If your FR‑S has aftermarket electrical accessories (audio, lights), consider disconnecting the positive terminal as well. Lift the front of the car using the factory jack points, then secure it on jack stands. Remove the engine undercover and drain the coolant—many supercharger kits require removal of the factory intake manifold or water pump bypass.

Safety Precautions

Working on a supercharger install involves pressurized systems, spinning belts, and engine coolant. Wear safety glasses when prying or torquing. Never use impact guns on aluminum fasteners—torque by hand. Keep a fire extinguisher rated for Class B (flammable liquids) and Class C (electrical) nearby. If you’re unfamiliar with fuel system work, disable the fuel pump via the fuse box before disconnecting any fuel lines.

Step‑by‑Step Installation Process

Step 1: Remove the Stock Intake System and Radiator Fan Shroud

Disconnect the MAF sensor and remove the air filter box. Unbolt the intake tube from the throttle body. You’ll also need to remove the upper radiator fan shroud to provide clearance for the supercharger belt routing—this is a common omission that trips up first‑timers. Set aside the intake components; you won’t reuse them.

Step 2: Drain Coolant and Remove the Radiator Overflow Tank

Crack the radiator drain plug (located on the lower left driver’s side) and drain coolant into a clean container. Then remove the two 10mm bolts securing the overflow tank. This opens up access to the right side of the engine bay where the supercharger bracket mounts. Plug the coolant lines to prevent debris ingress.

Step 3: Install the Supercharger Bracket

Most FR‑S supercharger brackets replace the factory alternator and power steering pump brackets. Clean the mounting surfaces on the engine block using brake cleaner. Apply a thin layer of blue Loctite to the bolts. Position the bracket and hand‑tighten all bolts before torquing to the specifications in your kit’s manual—typically 45–50 ft‑lb for M10 bolts. Use a cross‑pattern sequence to ensure even clamping.

Step 4: Mount the Supercharger Head Unit

Carefully lift the supercharger onto its bracket. Centrifugal units have a specific oil feed/return orientation; ensure the oil lines are not pinched. Positive‑displacement blowers are heavier—use a transmission jack or a helper. Secure the head unit with the supplied bolts (usually M8 or M10) and torque to the manufacturer’s spec. Double‑check clearances to the hood and radiator hoses.

Step 5: Install the Intercooler and Charge Piping

If your kit includes an air‑to‑air intercooler, mount it in front of the radiator. Use the provided brackets and rubber isolators to avoid vibration damage. Connect the charge pipes with silicone couplers and constant‑tension T‑bolt clamps. Ensure all connections are oriented so the pipes don’t contact any moving parts. For air‑to‑water systems, fill the coolant reservoir with a 50/50 mix of distilled water and antifreeze.

Step 6: Route the Supercharger Belt

The belt drives the supercharger from the crankshaft pulley. Loosen the belt tensioner (18mm bolt) and slide the belt onto the supercharger pulley, then route it per the diagram. Rotate the tensioner back to apply tension—typically 50–70 lbs of deflection pressure. A wobbly belt will slip; an overtightened belt can damage bearings. Use a belt tension gauge if available.

Step 7: Connect the Electrical Components

Reconnect the MAF sensor to the new intake piping. If your kit includes a boost controller or bypass valve solenoid, wire it according to the schematic. Run the positive wire from the supercharger’s intercooler pump (if installed) to a switched 12V source (e.g., the fog light relay). Land the ground wire on the strut tower bolt. Secure all wiring with zip ties away from heat sources and moving parts.

Step 8: Refill Fluids and Bleed the System

Reinstall the coolant overflow tank, refill the radiator with fresh coolant, and bleed air using the radiator cap and bleeder screw. Top off the supercharger’s oil reservoir if it uses a self‑contained lubrication system. Crank the engine with the fuel pump fuse removed for three seconds to prime the oil system, then reinstall the fuse.

Step 9: Reconnect the Battery and Initial Start‑Up

Reconnect the battery. Turn the ignition to “ON” without starting—listen for the fuel pump prime. Then start the engine. It may stumble for a few seconds as the ECU adapts. Let it idle for two minutes, then rev gently to 2500 RPM for 30 seconds. Check for oil leaks around the supercharger, coolant leaks at the intercooler, and boost/vacuum leaks at the charge pipes. Use a smoke machine if available—it’s the only reliable method to find small leaks.

Tuning and Calibration

A supercharger kit without proper calibration is a disaster waiting to happen. The FA20 engine’s high compression (12.5:1) requires precise fuel and ignition timing under boost. Use an ECUTek dongle and a professional tuner’s base map, or invest in a remote tune from a reputable shop like Delicious Tuning or Crawford Performance. Do not drive the car aggressively until the tune is finalized. Expect a baseline dyno session and one or two revisions. A proper custom tune will maximize reliability and power—most 8‑9 psi kits make 275–300 whp on 91‑octane fuel.

Performance Expectations

With a correctly installed and tuned supercharger kit, the transformation is dramatic. Here’s what you can expect:

  • Horsepower increase – from ~170 whp (stock) to 260–290 whp (low boost, 8–9 psi) or 330+ whp (high boost with fuel system upgrades).
  • Torque curve – a flat, broad torque plateau from 3500–7000 RPM, eliminating the stock FA20’s infamous torque dip.
  • Throttle response – instant with positive‑displacement blowers; slightly laggier but linear with centrifugals.
  • 0–60 mph times – drop from 6.2 seconds to the low‑5‑second range (stock tires) or sub‑5 seconds with sticky rubber.
  • Fuel economy – expect 21–24 mpg combined under normal driving; heavy boost will reduce it further.

Keep in mind that these gains come with increased heat load. Consider upgrading the radiator and adding an oil cooler—especially for track use. An aftermarket head unit with a tune can also push the stock clutch beyond its limit at higher power levels.

Common Questions and Maintenance

Do I need to upgrade the fuel system?

On stock fuel injectors and pump, boost above 9 psi risks fuel starvation. Most kits include 700–850 cc injectors and a 265 LPH fuel pump. For 10+ psi, you’ll need return‑style fuel regulation — consult your tuner.

How often do I check the supercharger oil?

Centrifugal units require oil changes every 30,000 miles or after every 10 dyno sessions. Positive‑displacement blowers are sealed; check for leaks annually.

Will this void my warranty?

Yes, completely. A supercharger install is not reversible without trace — the ECU flash leaves a counter that dealerships can detect. If you have remaining factory warranty, remove the kit and reflash the stock tune before any dealer visit.

What’s the best supporting mod for reliability?

A proper oil cooler (e.g., Setrab or Mocal) and a wideband O2 sensor with a gauge are the two most effective upgrades. Monitor oil temps and air/fuel ratio at all times. For more info on forced induction tuning, read this guide from FT86Club’s supercharger FAQ.

Conclusion

Installing a supercharger kit on your Scion FR‑S is a demanding but highly rewarding project. The key to success lies in meticulous preparation, following the kit’s instructions exactly, and investing in professional tuning. When done correctly, you’ll own a car that not only sounds spectacular but also pulls hard from every corner—transforming its personality without diminishing the chassis balance that makes the GT86 platform legendary. For those ready to take on the job, the result is a genuinely quick, reliable, and exhilarating sports car. For further reading on supercharger theory and installation tips, check out Supercharger Online for component details.