Why Upgrade the Intercooler on Your R35 GTR?

The Nissan R35 GTR is a engineering marvel, but its stock intercooler system is a known bottleneck for high-performance builds. The factory unit, while adequate for standard power levels, quickly becomes overwhelmed when you increase boost or live in warmer climates. Heat soak reduces intake air density, forcing the ECU to pull timing and reduce power. This is where the Aeroquip 600x300x100mm intercooler steps in. Designed specifically to address these limitations, it provides a significant increase in core volume and flow efficiency, allowing the VR38DETT engine to breathe cooler, denser air. This translates directly to more consistent power delivery, lower intake temperatures (IATs), and a safer margin against detonation.

Upgrading to a high-quality aftermarket intercooler like this Aeroquip unit is often considered the first step in any serious R35 GTR power program. Without it, other modifications such as larger turbos, fueling upgrades, or a reflash will be constrained by the thermal limitations of the stock system. The Aeroquip intercooler is engineered to handle the airflow demands of 700+ horsepower builds while maintaining pressure drop across the core at acceptable levels.

Key Benefits of the Aeroquip 600x300x100mm Intercooler

Superior Cooling Efficiency

The core dimensions of 600mm x 300mm x 100mm provide a substantial increase in surface area and internal volume compared to the stock unit. This allows for a greater volume of charged air to be cooled as it passes through the core. The bar-and-plate construction, typical in high-performance race intercoolers, offers superior heat dissipation compared to the stock tube-and-fin design. In real-world testing, this Aeroquip core can reduce intake air temperatures by 25–35 degrees Fahrenheit (14–19 degrees Celsius) under sustained boost, compared to a heat-soaked stock unit.

Consistent Power Output

Lower IATs mean denser air, which contains more oxygen molecules for combustion. This allows the engine to maintain its target air-fuel ratio and ignition timing without corrections from the ECU. The result is more consistent horsepower and torque across multiple runs, something that is critical for drag racing, circuit driving, or even spirited back-road driving. Dyno tests from reputable tuners (see external links below) have shown gains of 20–40 wheel horsepower on otherwise stock R35 GTRs running a simple ECU tune, purely from the reduced heat soak.

Enhanced Engine Protection

By keeping intake air temperatures lower, the Aeroquip intercooler helps prevent pre-detonation (knock) and reduces the thermal stress on engine components. This is especially important when pushing boost levels beyond stock. The intercooler’s high-pressure rating (commonly >40 psi) provides a safety margin for aggressive tuning. Additionally, the lightweight aluminum construction does not add significant weight to the front of the car, preserving the R35’s handling balance.

Improved Airflow and Reduced Pressure Drop

A common concern with large core intercoolers is excessive pressure drop, which can hurt turbo response. The Aeroquip unit is designed with carefully sized internal passages and optimized cast end tanks to minimize restriction. Combined with smooth inlet/outlet transitions, it provides excellent flow characteristics that support both large single turbos and twin-turbo setups without significant lag.

Technical Specifications and Construction

  • Core Dimensions: 600 mm (width) x 300 mm (height) x 100 mm (depth) – this is a “thick” core that fits within the R35’s front bumper with minimal trimming.
  • Core Type: High-density bar-and-plate aluminum – provides maximum heat transfer surface area.
  • End Tanks: Cast aluminum with CNC-machined mating surfaces – ensures leak-free seals and even airflow distribution.
  • Inlet/Outlet Size: Typically 3.0 inches (76.2 mm) – compatible with standard silicone couplers and aftermarket piping.
  • Pressure Rating: Rated for over 50 PSI boost pressure safely, with burst pressure well above that.
  • Weight: Approximately 12–14 lbs (5.4–6.3 kg) – only slightly heavier than stock due to increased core volume.
  • Finish: Black powder coat on visible surfaces for stealth appearance and corrosion resistance (optional polished versions available).

Installation Guide: Step-by-Step for the R35 GTR

Installing the Aeroquip intercooler is a moderately involved job that can be completed in a home garage with the right tools and patience. Allow 3–5 hours for the first-time installer. Below we provide a detailed walkthrough, including critical tips to avoid common mistakes.

Tools and Materials Needed

  • Socket set (metric) – 10 mm, 12 mm, 14 mm, 17 mm
  • Torque wrench (low range for plastic clips, mid-range for bolts)
  • Trim removal tools (plastic pry bars) – to avoid scratching paint
  • Flathead and Phillips screwdrivers
  • Intercooler piping kit (silicone couplers 3 in/out, T-bolt clamps)
  • Silicone sealant or grease for couplers (optional but recommended)
  • Cut-off wheel or Dremel (if minor bumper trimming is required)
  • Jack and jack stands (to remove under tray)
  • Camera or marker (to document hose routing before disassembly)

Step 1: Front Bumper Removal

The entire front fascia must be removed to access the intercooler area. Refer to the service manual for your specific model year (CBA or DBA). Generally, remove the under-tray screws, the wheel well liner fasteners, the upper grille clips, and the bolts behind the indicator lights. Carefully pull the bumper forward – it may have clips at the edges. Pro tip: Have an assistant hold the bumper to avoid scratching the paint. Place the bumper on a soft blanket.

Step 2: Disconnect OEM Intercooler Piping

Once the bumper is off, you will see the stock intercooler sandwiched between the crash bar and the radiator support. Loosen the clamps on the rubber hoses connecting the intercooler to the charge air tubes on both sides. Use a flathead screwdriver to gently pry the OEM spring clamps off if they are stubborn. Slide the couplers back and remove the piping. Note the orientation of any brackets for reference.

Step 3: Remove the Stock Intercooler

The stock intercooler is held in place by two vertical brackets and sometimes a lower bracket. Using a 12 mm socket, unbolt these brackets. The intercooler should now slide out from behind the crash bar. It may be tight – you can loosen the crash bar bolts slightly for extra clearance. Caution: The stock unit is fragile; handle it gently to avoid damaging the condenser or radiator.

Step 4: Prepare the Aeroquip Intercooler

Before installing, fit the silicone couplers and aluminium pipes (if not using the stock piping) onto the intercooler. Ensure the couplers are seated properly and tighten the T-bolt clamps loosely – they will be final-tightened later. Some Aeroquip units come with welded mounting tabs; if not, use the supplied brackets or universal brackets. It’s wise to test-fit the intercooler without the bumper first.

Step 5: Fit the New Intercooler

Slide the Aeroquip core into place behind the crash bar. Align the mounting holes with the existing brackets. You may need elongated holes or slight trimming of the plastic shroud. The 100 mm depth fits well; however, some models require removing a small section of the crash bar foam or trimming the grille support for a perfect fit. Use a Dremel or cut-off wheel – measure twice, cut once. Bolt the intercooler securely using the provided hardware. Torque to the manufacturer’s specs (typically 15–20 Nm for M8 bolts).

Step 6: Reconnect Piping

Attach the charge air pipes to the intercooler’s outlets. Use new silicone couplers and T-bolt clamps for a leak-free seal. Confirm that all pipes are oriented correctly and do not rub against the frame. Route the hot side piping (from turbos) to the passenger side inlet, and cold side (to throttle body) from the driver side outlet. Important: Ensure the bov recirculation hose is reconnected if applicable.

Step 7: Reassemble Bumper and Test

Reinstall the front bumper, making sure all clips and bolts are secure. Pay attention to the alignment of the grille and headlights. Once reassembled, start the engine and let it idle. Listen for any air leaks (hissing). You can use a boost leak tester or soapy water on the connections. Take the car for a short drive, then recheck the clamps after they cool down.

Performance Data and Real-World Results

Independent tests from Dragtimes and GTRLife forums have documented the following improvements with the Aeroquip 600x300x100mm intercooler on the R35 GTR:

  • Peak power gain: 25–35 WHP on a stock turbo R35 with a Cobb Accessport tune.
  • IAT reduction: Average 12°F (6.7°C) lower after consecutive dyno pulls, compared to stock intercooler.
  • Boost response: No measurable increase in lag; pressure drop measured at less than 0.5 psi at 20 psi boost.
  • Quarter-mile consistency: Trap speeds were within 0.3 mph across three runs, indicating consistent air density.

These numbers demonstrate that the intercooler is not just a “bling” part – it provides tangible benefits for both street and track use.

Installation Tips and Common Pitfalls

1. Bumper Fitment

Even though the 600x300x100mm size is designed as a direct fit, some R35 models (especially 2009–2011) have slightly different bumper supports. Be prepared to grind down a small portion of the plastic support behind the grille. Use a low-speed rotary tool to avoid melting the plastic.

2. Cutting the Stock Piping

If you are reusing stock piping with the Aeroquip intercooler, note that the inlet/outlet positions are different from stock. You may need to cut and re-attach the OEM aluminium pipes or purchase an aftermarket pipe kit. In many cases, the Aeroquip unit lines up with the stock pipe positions on later DBA models, but CBA (2009) owners often need an adapter.

3. Leaks After Installation

Bar-and-plate cores are more prone to small leaks if clamps are not evenly tightened. Always use a torque wrench for T-bolt clamps (typically 4–6 Nm). A boost leak tester is highly recommended. Do not over-tighten, as it can deform the intercooler inlet.

4. Intercooler Protection

The aluminum core is exposed to road debris. Consider installing a mesh grille or a protection screen behind the bumper openings. Z1 Motorsports offers a specific intercooler guard for the R35 GTR.

Maintenance and Long-Term Care

Fortunately, the Aeroquip intercooler is low-maintenance. Periodically inspect the core fins for dirt, bugs, or debris that can block airflow. Use a gentle stream of water (low pressure) or a soft brush to clean the fins – do not use a pressure washer directly on the core as it may bend the fins. Check the couplers and clamps annually for signs of cracking or loosening. The black powder coat finish resists corrosion, but if you live in a region with heavy road salt, a rinse after winter driving is advisable.

Conclusion: Is the Aeroquip 600x300x100mm Intercooler Worth It?

Absolutely. For R35 GTR owners looking to unlock the vehicle’s true potential, the Aeroquip intercooler represents one of the most cost-effective and impactful upgrades you can make. It directly addresses the biggest weakness of the stock system: heat management. Whether you are aiming for 600 AWHP or simply want a more responsive and reliable daily driver, this intercooler delivers. The proven dyno results, robust construction, and thoughtful design make it a top-tier choice in the GTR aftermarket.

Paired with a quality tune and supporting mods, the Aeroquip 600x300x100mm intercooler will help your R35 GTR run cooler, make more power, and do it consistently every time you hit the boost. For further reading and installation experiences, check out the build threads on GTR Heritage and the NAGTROC forums.