Tools and Materials Needed for the HKS 3.3T Turbo Upgrade

Before starting the upgrade on your Kia Stinger, ensure you have all necessary tools and materials. The HKS 3.3T turbo kit includes the turbocharger itself, gaskets, and hardware. You will also need:

  • Complete HKS 3.3T Turbo Kit (including oil and coolant lines)
  • Socket set (metric, 10mm to 19mm)
  • Torque wrench (capable of 20–80 lb-ft)
  • Flathead and Phillips screwdrivers
  • Combination wrenches (10mm, 12mm, 14mm, 17mm)
  • Oil catch can (recommended to reduce carbon buildup)
  • New exhaust manifold gaskets, turbo-to-manifold gasket, and downpipe gasket
  • Coolant (OEM spec or equivalent)
  • Engine oil (5W-30 fully synthetic, API SN or higher)
  • Thread locker (medium strength, blue)
  • Anti-seize compound for exhaust bolts
  • OBD-II scanner for post-install checks
  • Jack and jack stands (or a lift)
  • Shop towels and a drip pan
  • Torx bits (T30, T40) for some engine cover fasteners

Having all these items ready before you begin will streamline the process and prevent mid-job delays. For reference, consult the official HKS installation manual, which can be found on the HKS product page.

Preparation and Safety

Upgrading a turbocharger involves high temperatures and heavy components. Proper preparation ensures both safety and a clean installation.

Work Area and Vehicle Setup

  • Park the Kia Stinger on a level surface and engage the parking brake.
  • Disconnect the negative battery terminal. This prevents accidental short circuits and protects the ECU during disassembly.
  • Allow the engine to cool completely — the exhaust manifold and turbo can exceed 500°F after operation. A cool engine also makes handling gaskets easier.
  • Remove all engine covers, the air intake box, and the intercooler pipes that block access to the stock turbo. Use a Torx bit for the plastic covers.
  • Drain the coolant from the block using the drain plug on the passenger side (refer to your service manual) to avoid spills when disconnecting turbo coolant lines.

Pre-Installation Checks on the HKS Turbo

Inspect the HKS 3.3T turbo for any shipping damage. Spin the compressor and turbine wheels by hand — they should rotate freely with no binding or scraping. Check that the oil inlet and outlet ports are clean and free of debris. If your kit includes a wastegate actuator, verify the rod moves smoothly.

If you plan to run higher than stock boost (HKS recommends 12–15 psi on a stock engine), now is a good time to upgrade your fuel system and intercooler. For more info, check Stinger Forum community guides for supporting mods.

Removing the Stock Turbocharger

The stock turbo on the Kia Stinger’s 3.3L twin‑turbo Lambda II engine is compact. On a stock engine, there are two turbos — one per cylinder bank. The HKS 3.3T upgrade typically replaces one or both. This guide covers replacing the driver-side (bank 1) turbo; the procedure is mirrored for the passenger side.

  1. Remove the intake pipe from the stock turbo. Loosen the hose clamp at the compressor outlet and the connection to the air intake duct.
  2. Disconnect the exhaust downpipe from the turbo outlet. Use penetrating oil on the bolts if they are rusted. Four bolts typically hold the downpipe flange.
  3. Unplug electrical connectors — the wastegate actuator solenoid, boost pressure sensor, and possibly the oxygen sensor if it’s mounted near the turbine.
  4. Remove the oil feed line from the top of the turbo. Use a flare nut wrench to avoid rounding the fitting. Expect some oil drips.
  5. Disconnect the coolant lines — both supply and return. They are banjo bolt fittings. Have a rag ready.
  6. Unbolt the turbo from the exhaust manifold. Usually four or five bolts connect the turbine housing to the manifold. Use a breaker bar if needed.
  7. Carefully lift the stock turbo out of the engine bay. It may require tilting to clear the frame rail. The unit weighs about 15–20 lbs.
  8. Remove the old gaskets from the manifold and downpipe faces. Clean the mating surfaces with a razor blade and brake cleaner.

Inspect the removed turbo for any signs of oil leakage or shaft play. If your stock turbo was failing, now is the time to also flush the oil lines.

Installing the HKS 3.3T Turbo

The HKS 3.3T is a direct replacement but uses a larger compressor wheel and revised housing for higher flow. Follow these steps for a secure installation:

  1. Apply a thin layer of anti-seize to the exhaust manifold studs and new manifold-to-turbo gasket. Place the new gasket onto the studs.
  2. Position the HKS turbo so the turbine inlet aligns with the manifold. Be careful not to damage the gasket.
  3. Hand-thread the mounting bolts and then torque them to the HKS specified value — usually 35–40 lb-ft. Use a cross pattern to ensure even clamping.
  4. Attach the oil feed line to the top of the turbo. Use new copper washers on banjo fittings. Torque to 18 lb-ft (approximately 24 Nm).
  5. Connect the coolant lines. Again, use new gaskets. Torque banjo bolts to 15 lb-ft.
  6. Reattach the downpipe using a new gasket. Coat the downpipe bolts with anti-seize. Torque in sequence to 30 lb-ft.
  7. Plug in all electrical connectors — wastegate solenoid, pressure sensor, and O2 sensor if removed. Ensure the wire harness is routed away from hot surfaces.
  8. Install the new intake pipe provided in the HKS kit. This pipe may have a larger diameter to match the turbo outlet. Secure with T-bolt clamps.

If you are replacing both turbos, repeat the process on the opposite side. Note that the passenger side may require removing the intercooler or battery tray for access.

Connecting Additional Components and Vacuum Lines

The HKS turbo kit often includes a new wastegate actuator, blow‑off valve flange, and vacuum lines. Proper routing is critical for boost control.

Wastegate and Boost Controller Setup

Install the wastegate actuator to the turbine housing using the supplied bracket. Connect the actuator diaphragm hose to a boost source — typically a port on the compressor cover or a dedicated boost controller. If you are using an aftermarket electronic boost controller, follow its manual for solenoid installation.

For street driving, a boost level of 10–12 psi is safe on stock internals. Above 15 psi is recommended only with forged pistons and rods. The HKS kit comes with a spring that sets base boost; you can add a manual boost controller for fine-tuning. For detailed setup, see the HKS boost controller guide.

Oil Catch Can Installation

Upgraded turbos increase crankcase pressure. Installing an oil catch can between the PCV valve and intake helps prevent oil vapor from coating the intercooler and compressor wheel. Mount the can to the strut tower or firewall using a bracket. Run 5/8" hose from the PCV valve to the can’s inlet, and from the can’s outlet to a vacuum source on the intake pipe. Drain the can every oil change.

Reconnecting Vacuum Hoses

  • Check all rubber hoses for cracks — high boost can cause leaks.
  • Use silicone hoses for durability. Replace any crushed or collapsed lines.
  • Secure all connections with zip ties or hose clamps. A boost leak will cause poor performance and lean conditions.

Final Steps: Fluids, Battery, and Leak Check

After all mechanical connections are made, finish the job:

  1. Refill the coolant system using the manufacturer’s bleeding procedure. For the Kia Stinger, open the bleed screw on the thermostat housing until coolant streams out without bubbles.
  2. Fill the engine with fresh oil. Use 6.5 quarts of 5W-30 full synthetic. Start the engine with the oil cap off and watch for oil flow to the turbo feed line — this primes the turbo bearings.
  3. Reconnect the negative battery terminal.
  4. Start the engine and let it idle. Listen for unusual sounds — screeching (wastegate or belt), knocking, or exhaust leaks. Check around the turbo for oil or coolant drips.
  5. Bring the engine to operating temperature. The coolant fans should kick on twice. Shut off and recheck fluid levels.
  6. Inspect all clamps and bolts after the first heat cycle. Metal expands and can cause loosening.

Performance Testing and Tuning

With the HKS 3.3T installed, the Kia Stinger will spool differently than stock. The larger turbo may have slightly more lag but delivers stronger top-end power. To fully realize the upgrade, tuning is essential.

Using an OBD-II Scanner

Drive the car under light load for the first 50 miles. Then perform a hard pull in 3rd gear from 2500 rpm to redline. Scan for trouble codes. Common post‑upgrade codes include P0171 (lean) or P0234 (overboost). These indicate fuel or boost control issues that a custom tune can fix.

Consider Professional Tuning

Factory ECU calibrations are not designed for upgraded turbos. A tune from companies like LAP3 USA or Burger Tuning JB4 can adjust fuel trims, ignition timing, and boost targets. Expect 430–480 wheel horsepower on pump gas with the HKS 3.3T and proper supporting mods (downpipes, intercooler, fuel system).

Monitor boost pressure via a gauge or the OBD app. Keep peak boost around 14 psi for reliability. If you experience knock retard, back off the boost or increase the fuel octane.

Maintenance and Long-Term Care

Upgraded turbos require more frequent maintenance. Follow these guidelines:

  • Change oil every 3,000–5,000 miles with a high-quality synthetic. Turbo bearings wear faster with dirty oil.
  • Inspect the air filter monthly — a dirty filter starves the turbo.
  • Check the wastegate actuator rod for free movement during every oil change.
  • Listen for any change in spool sound — a hiss could indicate a boost leak.
  • Keep an eye on the oil catch can level and empty it as needed.

With proper care, the HKS 3.3T turbo will provide years of reliable increased power. Regularly visit Stinger Forum for community tips on maximizing the platform.

Conclusion

Installing the HKS 3.3T turbo on your Kia Stinger is a direct way to unlock significantly more horsepower while retaining drivability. Following this step-by-step guide — from preparation through final tuning — ensures a safe and effective upgrade. Take your time with gasket cleaning and torque specifications, and consider professional tuning to extract the full potential. The result is a Stinger that pulls harder through the midrange and top end, offering a driving experience that rivals far more expensive competitors.