Why Upgrade to a Mishimoto Intercooler for Your Boosted FA24?

For owners of the second-generation Subaru BRZ or Toyota GR86 with the FA24 engine who have added forced induction, the stock intercooler is often the first bottleneck. The FA24’s factory charge air cooling system is designed for the naturally aspirated configuration; after adding a turbocharger or supercharger, inlet air temperatures spike quickly, robbing power and increasing the risk of detonation. A high-flow, bar-and-plate intercooler like the Mishimoto unit offers significantly greater heat rejection, lower pressure drop, and better thermal recovery during back-to-back pulls. Upgrading to a Mishimoto intercooler not only helps maintain consistent horsepower but also improves engine safety and longevity under sustained boost.

The Mishimoto intercooler for the FA24 features a dense bar-and-plate core, cast-aluminum end tanks with smooth internal transitions, and T-slot brackets for a precise OEM-like fit. Unlike tube-and-fin designs, bar-and-plate cores manage heat more effectively and resist deformation under high boost pressures. With proper installation, you can reduce intake air temperatures by 30–50°F on a hot day, which translates directly into more dense air, better combustion, and safer engine operation.

Tools and Materials Needed

Before beginning, gather all necessary tools and supplies. Having everything on hand will prevent frustrating interruptions during the installation.

  • Mishimoto intercooler kit (part specific to 2022+ BRZ/GR86 turbo applications)
  • Socket set (metric, 8mm through 19mm, with extensions and a universal joint)
  • Wrench set (combination wrenches in 10mm, 12mm, 14mm, 17mm)
  • Torque wrench (capable of 20–50 ft-lb range)
  • Trim removal tools (plastic pry tools to avoid scratching paint)
  • Flathead and Phillips screwdrivers
  • Cutting tool (rotary tool or fine-tooth saw – only if trimming is required for charge pipe clearance)
  • Silicone spray or soapy water (for sliding silicone couplers onto pipes)
  • Thread locker (medium strength, blue) for bracket bolts exposed to vibration
  • Safety goggles and mechanic’s gloves
  • Jack and jack stands (not strictly required but helpful for bumper removal)
  • Rags and a catch pan (for any small coolant or oil drips if other work is done)

Preparation Steps

Start with the vehicle parked on a level surface, the engine completely cool, and the keys removed. Set the parking brake and chock the rear wheels. Disconnect the battery negative terminal – this eliminates any risk of accidentally triggering the electric cooling fans or shorting electrical connectors during disassembly.

Remove the Front Bumper

The front bumper assembly must come off to access the intercooler area. On the second-generation BRZ/GR86, the bumper is held by screws, push-clips, and a few hidden fasteners. Follow these steps carefully to avoid breaking tabs:

  1. Using a trim tool, pop out the covers over the tow-hook cutout and any access panels near the wheel well liners.
  2. Remove the Phillips screws and push-pin clips along the top edge of the bumper where it meets the hood latch panel.
  3. Remove the fasteners securing the bumper to each fender. There are typically two or three screws (8mm or 10mm) and a push-clip per side.
  4. Reach under the front bumper and remove the under-tray screws that secure the bumper to the lower lip of the radiator support.
  5. Carefully pull outward from the wheel wells to release the side clips, then gently tug the bumper forward. Unplug the fog light connectors (if equipped) and the front camera / sensor connectors (if applicable) before fully removing the bumper.
  6. Set the bumper on a clean, padded surface to prevent scratching the paint.

Tip: If you have a front splitter or aftermarket lip, remove it first to avoid binding.

Remove the Stock Intercooler

With the bumper off, you can see the factory intercooler mounted in front of the radiator. If your FA24 is a factory turbo application (e.g., GR Corolla or aftermarket turbo kit), the stock intercooler will be present. Note: the naturally aspirated BRZ/GR86 does not have an intercooler – this guide is for vehicles with an aftermarket or OEM turbocharger. If your car did not come with an intercooler, skip directly to the installation section and refer to your turbo kit’s instructions for charge pipe routing.

  1. Disconnect the charge pipe hoses from each end of the intercooler. Use a screwdriver to loosen the hose clamps, then wiggle the hoses free. Expect some residual oil or moisture to drip; have a rag ready.
  2. Unplug any electrical connectors attached to the intercooler (some kits integrate a temperature sensor or pressure sensor).
  3. Using a socket and ratchet, remove the four mounting bolts (typically 12mm or 14mm) that secure the intercooler to the radiator support or condenser brackets.
  4. Lift the stock intercooler straight out. It may be wedged between the condenser and the crash bar – tilt it slightly to clear the fan shroud.
  5. Set the stock intercooler aside. You may want to keep the OEM mounting brackets and rubber isolators in case the Mishimoto kit reuses them (some versions do).

Installing the Mishimoto Intercooler

Now that the area is clear, you can mount the new Mishimoto intercooler. The design is intended to be a straightforward replacement with minimal modification, but verify fitment with your specific turbo kit – some charge pipe routings require slight trimming.

Position and Secure the Intercooler

  1. Take the Mishimoto intercooler out of its packaging. Note that it is heavier than the stock unit due to the bar-and-plate core. Handle it carefully to avoid damaging the cooling fins.
  2. Offer the intercooler into position. It should align with the factory mounting holes on the radiator support crossmember. The T-slot brackets allow you to fine-tune the vertical and horizontal position for perfect centering.
  3. Insert the provided mounting bolts and washers. Do not fully tighten yet – leave them snug so you can adjust alignment after connecting the charge pipes.
  4. If the Mishimoto kit uses the factory rubber isolators, transfer those from the OEM unit onto the new intercooler’s brackets before bolting.

Connect the Charge Pipes

  1. Slide the silicone couplers from the Mishimoto kit onto the intercooler outlets. Apply a small amount of silicone spray or soapy water to the inside of the couplers to ease assembly.
  2. Attach the charge pipes from your turbo kit (or the Mishimoto charge pipes if included) to the couplers. Ensure the pipe ends are fully inserted into the coupler – typically 1 to 1.5 inches of engagement.
  3. Position the T-bolt clamps over the coupler ends, centered over the ridge of the pipe bead. Tighten the clamps evenly. Refer to the Mishimoto manual for the recommended torque (usually 40–50 in-lb). Over-tightening can crush the coupler.
  4. Verify that the pipes do not rub against the fan shroud, radiator, or frame. If clearance is tight, you may need to rotate the intercooler slightly using the T-slot brackets, or trim a small portion of the fan shroud with a rotary tool. Many FA24 turbo kits require trimming of the black plastic fan shroud for a clean pipe path. Mark the area with a pencil and cut only what is necessary.
  5. Tighten the intercooler mounting bolts to the torque specified in the Mishimoto instructions (commonly 15–20 ft-lb). Apply a drop of blue thread locker to prevent loosening from vibration.

Reconnect Sensors (If Applicable)

If your vehicle uses a charge air temperature sensor or MAP sensor in the intercooler plumbing, ensure the connector is securely reattached. Some Mishimoto intercoolers include a bung for an IAT sensor – plug the sensor into the designated location and verify the O-ring is seated.

Reassembly

Reinstall the Front Bumper

  1. Before reattaching the bumper, do a final check of all intercooler and charge pipe connections. Look for any loose clamps or contact points. Rotate the steering lock to lock to verify that the pipes do not pinch the wheel well liners.
  2. Reconnect any electrical connectors that were unplugged (fog lights, parking sensors, camera). Route the wiring carefully to avoid pinching.
  3. Position the bumper onto the car, aligning the tabs on the fenders and the clips along the hood latch panel. Push firmly to snap the side clips back into place.
  4. Install the fasteners in reverse order: start with the top screws and clips, then the fender screws, then the under-tray screws. Tighten all fasteners evenly.
  5. Reinstall the tow-hook cover and any wheel well liner clips that were removed.

Reconnect the Battery

Attach the negative battery terminal and tighten it securely. Double-check that the terminal is fully seated and that no loose strands of wire are exposed. A loose battery connection can cause erratic sensor readings and voltage spikes.

Post-Installation Checks

Before taking your BRZ or GR86 on the road, perform a thorough inspection and leak test.

Leak Check

With the engine off, pressurize the intake system using a boost leak tester (or a shop air regulator set to 10–15 psi). Listen for hissing at the intercooler couplings, charge pipe joints, and sensor bungs. Soapy water sprayed on the connections will reveal bubbles if there is a leak. Tighten clamps as needed. Do not exceed 20 psi – the silicone couplers are designed for boost but over-pressurizing while static can damage components.

Test Drive and Data Monitoring

Start the engine and let it idle for a minute, then rev it gently to check for any unusual sounds. Take a short test drive, gradually increasing boost. Monitor the following parameters via an OBD-II scanner or aftermarket gauge:

  • Intake air temperature (IAT2 or charge air temp) – should drop significantly compared to the stock intercooler under the same conditions.
  • Boost pressure – verify that the intercooler does not add excessive pressure drop. You should see the same peak boost (or 0.5 psi less, which is normal).
  • Coolant temperature – ensure the intercooler core does not block airflow to the radiator. In hot weather, monitor to confirm cooling system performance is adequate.

If everything checks out, enjoy the improved throttle response and consistent power delivery. The Mishimoto intercooler will allow you to run more aggressive timing and higher boost with a safer margin against knock.

Conclusion

Upgrading to a Mishimoto intercooler on your boosted FA24 BRZ or GR86 is one of the most effective modifications for managing charge air temperatures. The bar-and-plate core, precision-fit brackets, and quality hardware make installation straightforward for a moderately experienced DIYer. By following this step-by-step guide and taking the time to ensure all connections are leak-free, you can maximize the performance gains and reliability of your turbo or supercharged setup.

For further reading, consult the official Mishimoto product page for torque specs and warranty information. The FT86 Club forum has detailed build threads that document intercooler installations on the FA24 platform. Additionally, a visual guide like the Mishimoto FA24 intercooler install video can be a helpful supplement to this written walkthrough.

If you are uncomfortable cutting plastic fan shrouds or tuning an aftermarket ECU after the intercooler upgrade, consult a professional shop with experience on the FA24 platform. Proper installation and a conservative tune will protect your engine and deliver years of trouble-free boosted driving.