2009 Infiniti G37 Sedan Sport
The 2009 Infiniti G37 Sedan Sport represents a sweet spot in the G sedan's history, offering a compelling blend of performance, luxury, and driver engagement. It's a car that continues to hold appeal for enthusiasts, owners, and even hobby mechanics due to its relative simplicity compared to more modern vehicles while still packing a decent punch.
Engine and Drivetrain: The Heart of the Beast
At the core of the G37 Sport lies the VQ37VHR engine. This 3.7-liter V6 is a descendant of the venerable VQ engine family, known for its reliability and smooth power delivery. Think of it like the Toyota 2JZ-GTE found in the Supra, but without the turbos and tuned for a broader powerband. While the 2JZ is famous for its potential at high horsepower, the VQ37VHR emphasizes immediate throttle response and usable power in everyday driving.
Variable Valve Event and Lift (VVEL)
The "VHR" designation in VQ37VHR stands for "Variable Valve Event and Lift." This is Infiniti's version of variable valve timing and lift, similar to Honda's VTEC (Variable Timing and Lift Electronic Control) system found in cars like the Acura Integra Type R or the S2000. Instead of using a simple rocker arm and cam lobe profile switching, VVEL uses a continuously variable system. This means the lift and duration of the intake valves can be adjusted on the fly, allowing the engine to optimize airflow for both low-end torque and high-RPM horsepower.
For example, at low speeds, the valve lift is reduced, improving fuel economy and reducing emissions. At high speeds, the valve lift is increased, allowing more air into the cylinders for increased power.
The beauty of VVEL is its precision. It allows for a smoother transition between valve lift profiles compared to traditional VTEC systems, resulting in a more linear power delivery. You won't experience the sudden "kick" often associated with VTEC, but rather a seamless surge of power as the RPMs climb. The system uses an electric motor to precisely adjust the pivot point of rocker arms, allowing for infinite control over valve lift. This is significantly more complex than VTEC's oil pressure-driven system, which uses solenoids to switch between distinct cam profiles.
Transmission Options: Manual or Automatic?
The 2009 G37 Sport was available with either a 6-speed manual or a 7-speed automatic transmission. The manual is the choice for purists, offering precise shifts and direct control over the engine's power. It's a similar experience to driving a BMW E46 M3 with its legendary manual gearbox. The automatic, on the other hand, provides smooth and quick shifts, especially with its available paddle shifters. While not as engaging as the manual, the automatic is still a capable performer and offers better fuel economy.
The 7-speed automatic uses adaptive shift control (ASC), which learns the driver's driving style and adjusts shift points accordingly. Think of it as a slightly less sophisticated version of the adaptive transmissions found in modern Audis and BMWs. It anticipates your needs and shifts accordingly, making it suitable for both relaxed cruising and spirited driving. The automatic also features Downshift Rev Matching (DRM), which blips the throttle on downshifts to match engine speed with wheel speed, resulting in smoother and faster downshifts, preventing wheel lockup, especially during aggressive braking. This is a feature often found in performance cars like the Nissan 370Z.
Suspension and Brakes: Sport-Tuned Handling
The "Sport" in G37 Sport isn't just for show. It comes with a sport-tuned suspension that includes stiffer springs, firmer dampers, and a thicker rear stabilizer bar. This translates to a more responsive and controlled ride, with less body roll in corners. Imagine the difference between a standard Honda Accord and an Accord Coupe with the optional sport suspension – the G37 Sport offers a similar level of improvement over the base G37 sedan.
Double Wishbone Front Suspension
The G37 Sport uses a double wishbone front suspension, a design known for its superior handling characteristics. This type of suspension allows for better control of camber and caster angles, which are crucial for maintaining tire contact with the road during cornering. Many high-performance cars, such as the Corvette and the Porsche 911, utilize double wishbone suspension systems because they offer precise handling and stability.
Multi-Link Rear Suspension
The rear suspension is a multi-link design, which also contributes to the car's excellent handling. Multi-link suspensions offer a good balance of comfort and control, allowing for independent movement of each wheel, which helps to absorb bumps and maintain stability. Think of it like the rear suspension in a Mazda MX-5 Miata, designed to maximize grip and minimize unwanted suspension movement.
Sport Brakes
The G37 Sport features larger brakes than the base model, providing improved stopping power. These brakes are crucial for taming the car's performance and inspire confidence during spirited driving. The larger rotors and calipers dissipate heat more effectively, reducing brake fade under heavy use. Upgrading the brakes is a common modification for owners looking to further enhance the car's performance, drawing inspiration from brake upgrades on performance cars like the Subaru WRX.
Electronics and Interior: Luxury and Technology
The 2009 G37 Sport offers a comfortable and well-equipped interior. Standard features include leather seats, power accessories, and a premium audio system. The car also features a variety of electronic systems, such as Vehicle Dynamic Control (VDC), which helps to prevent skidding and loss of control. VDC is similar to Electronic Stability Control (ESC) systems found in many modern cars, like the Ford Mustang, and uses sensors to detect when the car is losing traction and applies the brakes to individual wheels to help the driver maintain control.
Intelligent Key with Push-Button Start
The Intelligent Key system allows you to unlock and start the car without using a traditional key. As long as the key fob is within range, you can simply press a button on the door handle to unlock the car and press the start button to start the engine. This is a convenient feature that is becoming increasingly common in modern cars, similar to keyless entry systems found in vehicles like the Hyundai Sonata.
Practical Takeaways for Owners and Hobby Mechanics
- VQ37VHR Engine Maintenance: The VQ37VHR is generally reliable, but regular oil changes with high-quality synthetic oil are crucial. Pay attention to the valve cover gaskets, as they are prone to leaking over time. Similar to many modern engines, proper oil maintenance is critical to avoid premature wear on components like the VVEL actuators.
- Transmission Fluid Changes: Regularly changing the transmission fluid, especially in the automatic, will help to prolong its life. Using the correct fluid type is critical to the proper operation of the transmission.
- Brake Maintenance: Inspect the brakes regularly for wear and tear. Consider upgrading to performance brake pads for improved stopping power, especially if you frequently drive aggressively. Ensure proper brake bleeding to maintain optimal brake performance.
- Suspension Inspection: Inspect the suspension components regularly for wear and tear, especially the ball joints and bushings. Replacing worn suspension components will improve handling and ride quality.
- VVEL System: While robust, the VVEL system can be sensitive to dirty or low oil levels. Ensure proper oil maintenance to prevent potential issues. If you notice any unusual engine behavior, such as rough idling or reduced power, have the VVEL system inspected by a qualified mechanic.
- ECU Tuning: While the stock engine is powerful, aftermarket ECU tuning can unlock even more performance. However, it's essential to choose a reputable tuner and ensure that the tune is optimized for your specific modifications.
The 2009 Infiniti G37 Sedan Sport is a rewarding car to own and maintain. Its combination of performance, luxury, and engaging driving dynamics makes it a standout in its class. By understanding its technical features and following proper maintenance procedures, owners can enjoy many years of trouble-free driving.