The Infiniti G35 remains one of the most popular platforms for affordable performance upgrades. With its VQ35DE engine—a 3.5-liter V6 known for its smooth powerband and robust construction—the G35 responds exceptionally well to forced induction. While many enthusiasts start with bolt-on modifications like intake and exhaust, the real leap in performance comes from adding a turbocharger. A properly designed turbo kit can push a stock internal G35 well past the 350-horsepower mark, transforming the car into a genuine high-performance machine. In this guide, we break down the best bolt-on turbo upgrades for the G35, focusing on proven kits from Greddy and Stillen, and cover everything from installation considerations to supporting modifications and tuning.

The VQ35DE Engine: A Foundation for Forced Induction

Before selecting a turbo kit, it's important to understand what you are working with. The VQ35DE in the G35 features an aluminum block and heads, a 10.3:1 compression ratio (depending on model year), and a robust bottom end. While the stock internals are generally capable of handling up to about 400–450 wheel horsepower on a well-tuned system, the factory compression ratio is slightly higher than ideal for big boost. Fortunately, most off-the-shelf bolt-on kits for the G35 are designed to work reliably with the stock engine, provided you stay within the recommended boost levels (typically 6–9 psi) and include proper engine management. The VQ35DE's strong cylinder head design and dual overhead cams also flow well, allowing turbo kits to make impressive power without extensive head work.

Turbocharging vs. Supercharging for the G35

Enthusiasts often debate between turbocharging and supercharging the G35. Superchargers—like the popular Vortech or Stillen supercharger kits—provide instant linear power and are easier to install, but they tend to cap out at lower peak horsepower due to parasitic loss and heat buildup. Turbocharging, on the other hand, offers greater peak power potential and efficiency. A turbo system uses exhaust energy to spin the compressor, meaning there is almost no parasitic drag on the engine. This allows for higher horsepower figures—often 350–450 whp on a stock block—with the right turbo and tuning. The trade-off is a more complex installation, increased heat management requirements, and the need for intercooling. For those chasing the 350+ horsepower target and beyond, turbocharging is the clear path.

Benefits of Adding a Turbocharger to Your G35

Upgrading to a turbocharger offers a range of performance and driving experience improvements:

  • Dramatic Horsepower Gains: A well-matched turbo kit can deliver 350–450 wheel horsepower on pump gas, nearly doubling the stock output.
  • Mid-Range Torque Surge: The torque curve on a turbocharged VQ35DE fills in much earlier and stronger than the naturally aspirated version, especially with a properly sized turbo like the GT2871R or GT3071R commonly used in these kits.
  • Aftermarket Support: Because the G35 shares its platform with the Nissan 350Z, there is a massive ecosystem of turbo components, intercoolers, piping, and tuning solutions available.
  • Improved Efficiency at Cruise: A turbo engine can maintain power with less throttle input, and modern tuning allows for very safe air/fuel ratios during light load, improving fuel economy over a naturally aspirated build with aggressive cams.

Top Bolt-On Turbo Kits for the Infiniti G35

When researching turbo upgrades for your G35, two names dominate the bolt-on marketplace: Greddy and Stillen. Both companies have produced kits specifically engineered for the VQ35DE chassis for well over a decade, and each has its own strengths.

Greddy Turbocharger Kit

Greddy (Trust) is a Japanese performance giant with decades of experience in forced induction. Their G35 turbo kit is widely considered one of the most complete and highest-quality bolt-on options available. The kit is designed to be a true bolt-on solution, meaning you do not need to cut or weld the factory subframe or oil pan—though some early G35 models may require a small oil pan modification for the drain.

  • Turbocharger: Typically uses a Greddy T518Z or T67 turbocharger, optimized for quick spool and safe boost levels.
  • Power Output: With the included boost controller and proper tuning, the Greddy kit reliably produces 350–400 wheel horsepower on 93-octane fuel.
  • Included Components: The kit comes with a cast iron exhaust manifold, a front-mount intercooler, blow-off valve, wastegate, all necessary piping, and oil lines.
  • Build Quality: Greddy uses high-grade stainless steel and cast iron, ensuring long-term durability under heat cycles.
  • Installation Difficulty: Moderate; some fabrications may be needed for later-model G35s, but overall the kit is designed for the home enthusiast with basic mechanical skills.

One key advantage of the Greddy kit is that it retains all factory accessories and air conditioning. The intercooler piping routes cleanly, giving the engine bay a relatively stock appearance. Many owners report that the Greddy kit feels OEM+ in terms of drivability once tuned correctly. For additional details, you can visit the official Greddy product page here: Greddy Performance.

Stillen Turbocharger Kit

Stillen, a well-known American aftermarket company based in California, has been supporting Nissan/Infiniti platforms for decades. Their turbo kit for the G35 is marketed as a "stage 2" system, designed to produce over 350 horsepower at the wheels with excellent reliability.

  • Turbocharger: Uses a Garrett GT3071R or equivalent, which is known for a broad power band and good durability.
  • Power Output: Stillen advertises 380–420 wheel horsepower on their standard tune, with higher numbers achievable via custom ECU calibration.
  • Included Components: The kit includes a cast manifold, a Tial-style wastegate, a large bar-and-plate intercooler, silicone couplers, oil feed/return lines, and a downstream MAF sensor pipe.
  • Supporting Electronics: Stillen includes a piggyback fuel computer (often a Split Second or AEM F/IC) to manage fueling and timing, though many users eventually upgrade to a standalone ECU like Haltech or Link for greater control.
  • Ease of Installation: Stillen’s kit is also a true bolt-on with no cutting of the chassis required.

The Stillen kit has a reputation for strong mid-range torque and excellent customer support. Stillen also offers complete Stage 3 packages that include upgraded injectors, fuel pump, and cams for those aiming at 450+ wheel horsepower. For more information, see the Stillen G35 turbo kit page: Stillen Performance.

Key Components of a Complete Turbo System

Understanding the parts in a turbo kit helps you evaluate quality and plan upgrades. Here are the critical elements:

  • Exhaust Manifold: Both Greddy and Stillen use cast iron units that resist cracking and hold heat correctly. Avoid cheap tube manifolds that can crack under thermal stress.
  • Turbocharger Core: Choose a turbo with a compressor map that matches your power goals. For the G35, a 60–70mm inducer is ideal for 350–400 whp with quick spool.
  • Wastegate: An external wastegate (typically 38–44mm) provides precise boost control. The kits include either a Tial or Greddy unit.
  • Blow-Off Valve (BOV): Both kits include a recirculating blow-off valve to maintain smooth idle and avoid compressor surge.
  • Intercooler: A front-mount intercooler (FMIC) is essential for keeping intake temperatures low. Greddy and Stillen provide quality bar-and-plate cores.
  • Oil and Coolant Lines: Proper oil supply and return are critical. The kits include theft-proof fitting kits.

Installation Considerations and Required Supporting Mods

Even with a bolt-on kit, certain supporting modifications are essential for reliability and performance. Here is what you need to plan for.

Fuel System Upgrades

Stock G35 injectors (rated around 280cc) and the factory fuel pump will max out near 300 wheel horsepower. To safely reach 350+ whp, consider upgrading to 550cc–750cc injectors (which are plug-and-play with appropriate resistors) and a Walbro 255 lph or AEM 340 lph fuel pump. Both Greddy and Stillen sell optional fuel system upgrades, or you can buy components separately.

Engine Management and Tuning

Tuning is the single most critical factor for a turbocharged G35. The stock ECU can be reflashed if you have the correct software (e.g., UpRev or EcuTek), but most turbo kits recommend a standalone or piggyback system. Stillen includes a piggyback, while Greddy requires an aftermarket ECU such as a Haltech Elite or AEM Infinity. Professional dyno tuning is highly recommended to dial in boost response, fuel mapping, and ignition timing. Many tuners have base files for these kits, saving time and ensuring safe operation. For tuning resources, you can check out Z1 Motorsports for software and parts.

Exhaust and Cooling

A turbo kit typically includes a downpipe that connects to your existing cat-back exhaust. However, the stock exhaust is restrictive; a 3-inch cat-back system is recommended to reduce backpressure and improve spool. Also consider upgrading the radiator and adding an oil cooler to manage heat. The VQ35DE runs warm under boost, and consistent cooling is key to long engine life.

Cost Breakdown: What to Expect

Building a reliable 350+ whp G35 is not cheap. Here is a rough estimate:

  • Turbo Kit (Greddy/Stillen): $3,500 – $4,500
  • Fuel System (injectors, pump, lines): $500 – $1,000
  • Engine Management and Tuning: $1,200 – $2,500
  • Exhaust (cat-back): $500 – $800
  • Cooling Upgrades (radiator, oil cooler): $600 – $1,200
  • Professional Installation (if not DIY): $1,000 – $2,000

Total budget: approximately $7,000 – $11,000 for a turnkey 350+ whp build. Many owners offset costs by doing the installation and tuning themselves with guidance from online communities like G35 Driver Forums.

Reliability and Maintenance Tips

A turbocharged G35 can be perfectly reliable if built and maintained correctly. Follow these guidelines:

  • Use High-Quality Oil: Synthetic 5W-30 or 10W-40 with frequent changes (every 3,000–4,000 miles).
  • Allow Warm-Up and Cool-Down: Idle the engine for 30–60 seconds after a hard run to allow the turbo to cool.
  • Monitor Boost and AFR: Install a wideband oxygen sensor and boost gauge to catch issues early.
  • Check for Leaks: Vacuum and boost leaks can cause lean conditions; inspect couplers and clamps regularly.
  • Consider a Catch Can: The VQ35DE can push oil vapor into the intake under boost; a catch can keeps the intercooler clean.

Conclusion

Turbocharging your Infiniti G35 with a bolt-on kit from Greddy or Stillen is a proven path to over 350 horsepower. These kits are engineered to work with the stock VQ35DE engine, offering excellent drivability and reliability when installed with proper supporting mods and a quality tune. Whether you choose the Greddy system for its Japanese engineering and completeness or the Stillen kit for its American support and proven power, both options will transform your G35 into a genuinely fast sports car. Plan your budget carefully, invest in professional tuning, and you will have a thrilling machine that holds its own against modern performance vehicles.