Upgrading the intake system on your Infiniti G37 is one of the most effective ways to unlock additional horsepower, sharper throttle response, and a more aggressive engine note. The JWT Pop Charger has gained a strong reputation among G37 enthusiasts as a reliable, high-flow cold air intake that delivers noticeable gains without breaking the bank. This comprehensive guide will walk you through everything you need to know about the JWT Pop Charger, from what it is and why it works, to a detailed installation procedure, complete cost breakdown, and realistic performance expectations. Whether you are a seasoned DIYer or a first-time modder, this article provides authoritative, hands-on advice to help you make an informed decision and execute the installation with confidence.

What is the JWT Pop Charger?

The JWT Pop Charger is a performance air intake system developed by Jim Wolf Technology, a respected name in Nissan and Infiniti performance engineering. Unlike generic “short ram” intakes, the Pop Charger is engineered specifically for the VQ37VHR engine found in the Infiniti G37. It replaces the restrictive factory air box with a large, conical K&N-style high-flow filter mounted directly on the mass airflow (MAF) sensor housing. The design is intentionally simple: by removing the factory resonator and air box restrictions, the engine can draw in cooler, less turbulent air, improving volumetric efficiency. The filter itself is oiled cotton gauze, washable and reusable, offering excellent filtration while allowing high airflow.

The kit includes a CNC-machined aluminum MAF adapter, stainless steel hardware, and a heat shield (on certain model years) to minimize heat soak. The result is a intake that flows significantly more air than stock, supporting power gains across the entire rpm range.

Benefits of Installing a JWT Pop Charger

Upgrading to a JWT Pop Charger provides a blend of performance, sound, and reliability benefits that make it a popular first mod for G37 owners. Below are the key advantages with detailed explanations.

  • Increased horsepower and torque: By reducing intake restriction, the engine can breathe easier. Dyno tests from independent tuners show gains of 10–15 wheel horsepower and 8–12 lb-ft of torque on a normally aspirated G37. The gains are most noticeable in the mid-range and top end, where the stock intake tends to choke airflow.
  • Sharper throttle response: The reduced intake volume and elimination of resonators mean the engine reacts more quickly to pedal inputs. Part-throttle acceleration feels more immediate, and the car feels livelier in daily driving.
  • Improved engine sound: The VQ37VHR engine has a naturally aggressive tone. With the Pop Charger, induction noise becomes louder and more pronounced, especially above 4,000 rpm. Many owners describe a deep, throaty growl that enhances the driving experience without being obtrusive at cruise.
  • Better fuel efficiency potential: While not a primary goal, improved airflow can lead to more complete combustion, which may yield slight gains in fuel economy under normal driving. Actual results vary based on driving habits and tuning.
  • Easy maintenance: The washable filter eliminates the need for frequent replacements. With proper cleaning every 30,000–50,000 miles, the Pop Charger can last the life of the vehicle.
  • OEM-fit quality: JWT’s parts are designed to bolt on using factory mounting points, requiring no cutting or modifications. The included heat shield (when applicable) helps keep intake air temperatures lower than a fully open short ram.

Tools and Materials Required

Before beginning the installation, gather the following tools and supplies. Having everything ready will streamline the process and prevent mid-job trips to the hardware store.

  • 10mm and 12mm sockets with ratchet and extension
  • Flat-head screwdriver (for prying hose clamps)
  • Phillips screwdriver (size #2)
  • Torque wrench (inch-pound range for MAF sensor bolts)
  • Needle-nose pliers
  • Shop towels or clean rags
  • MAF sensor cleaner (optional but recommended)
  • Zip ties (for securing hoses or wiring)
  • Flashlight or work light
  • Penetrating oil (if bolts are rusty)
  • Vacuum cleaner with crevice tool (to clean air box area before removal)
  • Safety glasses and gloves

Pre-Installation Preparation

Proper preparation ensures a smooth installation and protects sensitive engine components. Follow these steps before touching any bolts.

  1. Park the vehicle on a level surface and allow the engine to cool completely. A hot engine can cause burns and make plastic components brittle.
  2. Disconnect the negative battery terminal using a 10mm wrench. This will prevent accidental short circuits and reset the ECU’s learned fuel trims, helping the car adapt to the new intake more quickly.
  3. Clean the area around the factory air box. Use a vacuum or shop towel to remove loose dirt, leaves, and debris. This prevents contaminants from falling into the intake tract when the air box is removed.
  4. Inspect the factory intake system for any cracks, loose clamps, or damaged hoses. Replace any worn parts before installing the new intake.
  5. Lay out all JWT Pop Charger components and verify that the kit includes the filter, MAF adapter, hardware, and heat shield (if applicable). Refer to the included instructions for your specific model year.

Step-by-Step Installation Procedure

The following steps apply to 2008–2013 Infiniti G37 coupe and sedan models with the VQ37VHR engine. Sedans with the 7-speed automatic may have slight differences in hose routing, but the core process remains the same.

Step 1: Remove the Factory Air Intake

Start by loosening the hose clamp at the throttle body elbow using a flat-head screwdriver or a nut driver. Disconnect the rubber intake tube from the throttle body. Next, unplug the MAF sensor electrical connector by pressing the release tab and pulling straight up. Carefully remove the air box cover by prying the clips or removing retaining screws. Lift the entire factory air box assembly out of the vehicle.

You may need to gently wiggle it free from the lower rubber grommets. Remove the lower air box half if it is accessible, but on the G37, the lower section is often fixed; leave it in place if it does not interfere.

Step 2: Remove the MAF Sensor from the Factory Housing

Using a Phillips screwdriver, remove the two screws that secure the MAF sensor to the factory intake tube. Carefully pull the sensor straight out. Avoid touching the delicate sensing element; if it appears dirty, gently clean it with dedicated MAF sensor cleaner and let it dry completely. This step is critical for accurate air/fuel ratio readings after the new intake is installed.

Step 3: Install the MAF Adapter

The JWT kit includes a machined aluminum adapter that replicates the factory MAF housing diameter and sensor location. Install the supplied rubber O-ring onto the adapter, then insert the MAF sensor into the adapter. Secure it with the original screws. Torque to 15–20 in-lb (do not overtighten). Slide the adapter onto the throttle body elbow using a high-quality silicone coupler and T-bolt clamp.

Position the adapter so that the MAF sensor is oriented correctly (typically at a 10 or 2 o’clock angle to avoid interference). Hand-tighten the clamp.

Step 4: Mount the Filter and Heat Shield

Attach the conical K&N filter directly to the MAF adapter. Some JWT kits include a stainless steel support bracket that bolts to an existing threaded hole on the engine block; install this bracket first. Slide the filter onto the adapter and secure it with the provided clamp. If a heat shield is included, mount it using the supplied bracketry. The heat shield helps separate the intake from hot engine bay air, preserving density for better power.

Verify that the filter and heat shield do not contact any moving parts or sharp edges.

Step 5: Reconnect Hoses and Electrical Connectors

Reattach any vacuum lines or crankcase vent hoses that were disconnected during removal. The G37 typically has a small hose that connects to the factory intake tube; route it to the provided fitting on the JWT adapter if included, or plug it with a rubber cap. Reconnect the MAF sensor electrical connector and ensure it clicks securely. Use zip ties to tidy up any loose wiring or hoses.

Step 6: Final Checks and ECU Reset

Double-check all clamps, bolts, and connections. Ensure the filter is firmly attached and the heat shield is not rattling. Reconnect the negative battery terminal. Start the engine and allow it to idle for 3–5 minutes; the idle may be slightly rough at first while the ECU relearns. Rev the engine gently a few times to listen for any air leaks (hissing or whistling sounds).

If everything sounds normal, take the car for a short, gentle test drive. A full ECU drive cycle (about 50 miles) is needed for the engine to fully adapt and deliver peak performance.

Cost Breakdown

The total cost of installing a JWT Pop Charger on your Infiniti G37 depends on whether you perform the work yourself or hire a professional. Below is a detailed breakdown of typical expenses as of 2025.

  • JWT Pop Charger Kit: $249–$359 depending on vendor and whether the kit includes a heat shield. Prices from Z1 Motorsports and Concept Z Performance are competitive.
  • Shipping & tax: $15–$35 for standard ground shipping within the U.S.
  • Labor (professional installation): $100–$180 at an independent shop; dealer rates are higher. The job takes about 1–1.5 hours.
  • Miscellaneous parts and supplies: $10–$25 for MAF sensor cleaner, extra zip ties, or replacement clamps if factory hoses are brittle.
  • Optional tuning/ECU reflash: $400–$800 for a professional tune (e.g., ECUTek or UpRev). While not required, tuning maximizes the gains from the intake and ensures optimal air/fuel ratios. Many owners run the Pop Charger on the stock tune without issues.
  • Total DIY cost (kit + misc): $260–$395.
  • Total professional install (kit + labor + misc): $375–$550.
  • Total with tuning: $850–$1,350.

Most G37 owners find that the DIY route is straightforward and cost-effective. The only special tool required is a torque wrench for the MAF sensor bolts, but a careful hand can suffice.

Performance Expectations: Dyno Results and Real-World Driving

The JWT Pop Charger is not a magic bullet, but it delivers measurable, repeatable gains. Independent dyno tests on a stock 2009 Infiniti G37 coupe show peak gains of +12 horsepower and +10 lb-ft of torque at the wheels. More importantly, the power curve maintains a 8–15 hp advantage from 4,500 rpm to redline. The torque increase is most pronounced between 3,000 and 5,500 rpm, making the car feel stronger during daily merging and passing.

In real-world driving, the improved throttle response is immediately noticeable. The car no longer hesitates when you stab the throttle; instead, it reacts almost instantly. The intake sound becomes more aggressive, especially under wide-open throttle, but remains subdued at highway speeds. Some owners report a slight drop in low-rpm torque below 2,500 rpm due to the loss of the long intake tube’s resonance tuning, but this is minimal and offset by the gains everywhere else. Overall, the Pop Charger transforms the G37’s character without making it feel overly loud or unrefined.

Common Installation Mistakes and How to Avoid Them

Even experienced DIYers can encounter pitfalls. Avoid these common errors to ensure a trouble-free installation.

  • Forgetting to disconnect the battery: Failing to reset the ECU can cause a lean or rich condition initially, leading to poor drivability. Always disconnect the battery before starting.
  • Overtightening MAF sensor screws: The MAF housing is aluminum; stripping the threads is easy. Use a torque wrench or tighten gently by feel.
  • Loose or crooked MAF sensor: If the sensor is not fully seated, the airflow reading will be inaccurate, causing dips in power and potential check engine lights. Ensure the O-ring is properly placed and the sensor is flush.
  • Ignoring vacuum leaks: A hissing sound after installation indicates an unplugged vacuum line or loose clamp. Double-check every connection, especially the small hose near the throttle body.
  • Using improperly cleaned filter oil: Over-oiling the K&N filter can contaminate the MAF sensor. Use the spray oil sparingly and allow it to wick overnight before installation.
  • Skipping the heat shield: Without a heat shield, hot engine air can decrease power. Install the included shield or fabricate one if your kit does not include it.

Maintenance and Cleaning

The JWT Pop Charger requires periodic maintenance to continue performing at its best. The K&N filter should be cleaned every 30,000–50,000 miles (or more often if you drive in dusty conditions). Purchase a K&N Recharger kit (part #99-5000) containing cleaner and oil. Remove the filter, spray it with cleaner, let it sit for 10 minutes, rinse with low-pressure water from the inside out, and allow it to dry completely. Then apply the oil evenly along the pleats.

Reinstall the filter after 6–8 hours of drying time. Inspect the MAF sensor annually and clean it with MAF cleaner if you notice oil residue. Check all clamps and hoses for tightness every oil change.

Comparison with Other G37 Intakes

The JWT Pop Charger competes with popular options like the Stillen Gen 3 intake, Injen SP series, and AEM dry flow intakes. Here is how it stacks up.

  • JWT Pop Charger vs. Stillen Gen 3: Stillen’s intake uses a dual-filter, enclosed box design with a larger MAF housing. It typically makes slightly more peak horsepower (2–5 hp) but costs $150–$200 more and is more complex to install. JWT is simpler, cheaper, and easier to maintain.
  • JWT Pop Charger vs. Injen SP: Injen’s intakes include a polished aluminum tube and a dry flow filter. They offer similar gains but are more prone to heat soak without a heat shield. JWT’s optional heat shield and washable filter give it a durability advantage.
  • JWT Pop Charger vs. AEM DryFlow: AEM uses a dry filter that never needs oiling, which some prefer to avoid MAF contamination. However, AEM filters tend to clog faster in dusty environments and may require more frequent cleaning. JWT’s oiled filter provides slightly better airflow when clean.

For the majority of daily drivers and street enthusiasts, the JWT Pop Charger offers the best balance of cost, performance, and ease of use. It is a proven, time-tested upgrade that has been on the market for years with overwhelmingly positive feedback from the G37 community.

Conclusion

Installing a JWT Pop Charger on your Infiniti G37 is one of the most rewarding modifications you can make. The installation is straightforward, the cost is reasonable, and the performance gains are both audible and measurable. With 10–15 additional horsepower, sharper throttle response, and a more exciting engine sound, the Pop Charger transforms the driving experience without sacrificing reliability or daily drivability. Whether you install it yourself in an afternoon or have a shop do it, this intake is a worthwhile investment that will continue to pay dividends every time you press the accelerator. For further reading and to purchase the kit, visit JWT’s official website or trusted retailers like Z1 Motorsports.

Remember to follow the maintenance schedule to keep your Pop Charger performing at its peak for years to come.