The Nissan GT-R is a legendary performance machine, its twin-turbo V6 capable of immense power when properly modified. While the stock turbos are robust, they quickly become the limiting factor for owners chasing big horsepower. Upgrading to a TiAL Q Series turbo addresses this bottleneck, offering a proven path to significantly higher output while maintaining excellent drivability. This guide covers the turbo's design philosophy, a detailed installation roadmap, and the performance gains you can realistically expect from this upgrade.

Understanding the TiAL Q Series Turbocharger

TiAL Sports has earned a reputation for building high-quality turbochargers and wastegates, and the Q Series is a direct reflection of their engineering focus. Unlike many "off-the-shelf" turbos, the Q Series is designed specifically to replace the factory units in vehicles like the GT-R (R35) with minimal fabrication. It features a billet compressor wheel and a high-flow turbine housing optimized for quick spool and high top-end flow.

Key Design Features

  • Billet Compressor Wheel: CNC-machined from a solid billet of aluminum for superior strength, balance, and aerodynamic efficiency compared to cast wheels. This translates to higher boost capacity and faster response.
  • Advanced Turbine Geometry: The Q Series uses a turbine housing designed to reduce backpressure while maintaining excellent spool characteristics. The result is a turbo that feels responsive on the street yet supports substantial horsepower on the dyno.
  • Premium Materials: Full 304 stainless steel turbine housings (V-band inlet/outlet) resist corrosion and cracking under extreme heat. The center housing is water-cooled and oil-lubricated for long-term durability.
  • Direct Fitment (with kit): While the turbo itself is not a direct bolt-on to the GT-R's factory manifold without modifications, TiAL provides adapter kits and specific configurations (such as the Q67 and Q78) that are widely used in the R35 community. These typically require upgraded downpipes and intake piping.

The Q Series is available in several trims, such as the Q67 and Q78, with different compressor and turbine A/R options. For a GT-R, the Q67 is a popular choice for those targeting 700-850 whp on pump gas or E85, while the Q78 can support 900+ whp with the right supporting modifications.

Installation Process

Installing a TiAL Q Series turbo on a GT-R is not a beginner-level job. It requires mechanical experience, the correct tools, and preferably a lift. Plan for 1-2 days of labor if working alone. Always disconnect the battery and allow the engine to cool completely before starting.

Tools and Equipment Needed

  • Socket set (metric, including 10mm, 12mm, 14mm, 17mm, 19mm)
  • Wrenches (combination and flare nut for oil lines)
  • Torque wrench (ft-lb and in-lb ranges)
  • Pickle fork or ball joint separator (for O2 sensor bungs)
  • Oil catch can or drain pan
  • New gaskets and o-rings (manifold, turbo inlet, outlet)
  • V-band clamps (if not included with turbo kit)
  • Anti-seize compound and high-temp thread locker
  • Boost gauge and boost controller (recommended)
  • Jack stands or lift

Step-by-Step Installation Guide

  1. Preparation and Safety: Disconnect the negative battery terminal. Drain the engine oil and coolant if you will be disconnecting oil/water lines at the turbo. Remove the engine undercover and any components blocking access to the turbos (intake pipes, heat shields, front sway bar may need loosening).
  2. Remove the Stock Turbo: Unbolt the downpipe from the turbo outlet. Disconnect the oil feed and return lines, as well as the coolant lines. Remove the V-band or bolt connections securing the turbo to the manifold. Carefully lift the stock turbo out from the engine bay. Inspect the manifold for cracks or debris.
  3. Prepare the TiAL Q Series Turbo: Prime the turbo by pouring a small amount of clean engine oil into the oil feed port and rotating the compressor wheel by hand. This prevents dry start damage. Install the supplied V-band flanges and any adapter plates onto the turbo and manifold.
  4. Install the New Turbo: Position the TiAL turbo onto the exhaust manifold. Use new gaskets on all mating surfaces. Tighten the V-band connections evenly to the manufacturer’s torque specification (typically 50-60 in-lb for small V-bands). Secure the manifold to turbo bolts with high-temp thread locker.
  5. Connect Oil and Coolant Lines: Use the oil feed and return lines supplied with the kit or aftermarket lines designed for the Q Series. Ensure the oil return line has a continuous downward slope to the pan. Install the coolant lines (if water-cooled) and bleed the system to prevent air locks.
  6. Route Intake and Boost Piping: Connect new silicone intake hoses and charge pipes. The TiAL turbo typically uses a 4-inch inlet; you will need an intake kit with a larger filter. Install the boost reference line for the wastegate and boost controller.
  7. Reinstall Components: Reattach downpipes (must be compatible with V-band outlet). Reconnect oxygen sensors and any wiring. Refill engine oil and coolant. Check for leaks at all joints.
  8. Final Checks and Testing: Reconnect the battery. Start the engine and let it idle for a few minutes to circulate oil. Inspect for oil or coolant leaks. Once confirmed, take a short test drive (< 10 psi boost) then re-torque all V-band clamps and bolts after a heat cycle.

Supporting Modifications

Simply bolting on a larger turbo will not yield safe power without supporting upgrades. The factory fuel system, intercooler, and ECU tuning are critical.

  • Fuel System: At 700+ whp, the stock fuel pump and injectors are inadequate. Upgrade to a dual-pump setup (e.g., Walbro 525s) and larger injectors (at least 1300cc for E85).
  • Intercooler: The factory intercooler struggles with heat soak at higher boost. A front-mount intercooler upgrade is strongly recommended.
  • Engine Management: A custom ECU tune via Cobb Accessport or EcuTek is mandatory. The tuner will adjust timing, fuel, and boost targets to match the Q Series’ airflow characteristics.
  • Intake and Exhaust: A high-flow intake system and a 3-inch or larger exhaust reduce backpressure and help the turbo breathe.

Performance Gains

Upgrading to a TiAL Q Series turbo transforms the GT-R's power delivery. The gains are not just peak numbers but also improved response across the rev range.

Expected Horsepower and Torque

  • TiAL Q67 ( ~ 67mm compressor): With proper supporting mods (fuel, intercooler, tune), expect 700-800 whp on pump gas and up to 850+ whp on E85. Torque peaks around 650-700 lb-ft.
  • TiAL Q78 ( ~ 78mm compressor): For those targeting higher numbers, the Q78 can produce 850-950 whp on E85 with upgraded internals. Torque exceeds 800 lb-ft.
  • Spool Characteristics: Unlike many large turbos, the Q series spools relatively quickly. Full boost (20-25 psi) can be achieved by 3800-4200 rpm, depending on exhaust setup and tune. This is faster than many competitors in the same power range.

Driving Experience

On the road, the TiAL Q Series makes the GT-R feel more responsive in the mid-range. The improved turbine design reduces lag compared to older hybrid turbos. The car pulls hard to redline without falling off, giving the driver confidence at high speeds. Throttle response during corner exit is noticeably sharper, making the car easier to control under power.

Reliability Considerations

TiAL turbos are known for durability, but the increase in boost and heat will stress other components. Use high-quality synthetic oil, monitor oil temperatures, and consider an oil cooler upgrade. Regularly inspect turbine wheels for cracks or foreign object damage.

Conclusion

Installing a TiAL Q Series turbo on your Nissan GT-R is one of the most effective ways to unlock serious horsepower without sacrificing daily drivability. The turbo's advanced billet wheel design and efficient housing deliver strong gains from 700 to 950 whp, depending on configuration and supporting modifications. The installation requires mechanical skill and patience, but the reward is a GT-R that drives with authority and responds instantly to throttle inputs. For those ready to push beyond the factory limits, the TiAL Q Series is a proven choice.

For more technical details, visit TiAL's official product page for the Q67 turbo or the Q78 turbo. For community dyno results and installation tips, the GT-R forums at GTRLife are an excellent resource.