The Infiniti G35 established itself as a formidable player in the luxury sport sedan segment thanks in no small part to its powerful and refined engine. This comprehensive guide delves into the world of the G35 engine, exploring its various iterations, performance characteristics, common maintenance needs, and potential upgrade options. Whether you’re a seasoned G35 owner or considering one for your next car, this article equips you with the knowledge to understand, maintain, and potentially enhance the driving experience offered by this iconic engine.

A Tale of Two Engines: Unveiling the G35 Powerplants

The Infiniti G35 boasts two distinct engine options across its production years (2003-2008):

• VQ35DE: Introduced in the early years of the G35 (2003-2006), the VQ35DE is a 3.5L naturally aspirated V6 engine. This engine delivers a healthy balance of power and fuel efficiency, producing 280 horsepower and 260 lb-ft of torque in its most potent iteration.
• VQ35HR: Debuting in the 2007 model year, the VQ35HR is a refined version of the VQ35DE. This engine features a revised valve timing system, higher compression ratio, and electronic throttle control, resulting in increased power output (300 horsepower) and a more responsive driving experience.

Both the VQ35DE and VQ35HR engines are renowned for their smooth operation, throaty exhaust note, and durability. They have rightfully earned a reputation for delivering a thrilling driving experience while remaining practical for everyday use.

Under the Hood of Power: Specifications and Features of the G35 Engine

Here’s a closer look at the key specifications and features of both G35 engines:

• Engine Layout: VQ-series 60-degree V6
• Displacement: 3.5 L (213 cu in)
• Horsepower: (VQ35DE) 280 hp @ 6,200 rpm; (VQ35HR) 300 hp @ 6,800 rpm
• Torque: (VQ35DE) 260 lb-ft @ 4,800 rpm; (VQ35HR) 261 lb-ft @ 4,800 rpm
• Valvetrain: DOHC (Double Overhead Camshaft) with VVEL (Variable Valve Event Lift) on the VQ35HR
• Fuel System: Sequential multi-point electronic fuel injection
• Material: Aluminum block and cylinder heads

The VQ35HR engine incorporates several advancements over the VQ35DE, including the aforementioned VVEL system. VVEL optimizes valve timing and lift based on engine speed and load, enhancing both performance and fuel efficiency. Additionally, the VQ35HR features a revised intake system and electronic throttle control for sharper throttle response and a more engaging driving experience.

The G35 Engine: Performance on the Road

The G35 engine is a key contributor to the car’s reputation for exhilarating performance. Here’s a glimpse into what you can expect:

• Responsive Power Delivery: Both engine options offer satisfying acceleration, with the VQ35HR providing a slight edge due to its increased power output.
• Balanced Handling: The G35’s well-balanced handling complements the engine’s power. The rear-wheel-drive layout (with optional all-wheel drive) and near-perfect weight distribution provide a sporty and engaging driving experience.

• Signature Soundtrack: The G35 engine produces a throaty and satisfying exhaust note, particularly when pushed hard. This adds to the overall driving pleasure and reinforces the car’s sporty character.

While known for its exhilarating performance, the G35 engine also delivers respectable fuel efficiency for a car in its class. Fuel economy figures vary depending on the specific engine option, model year, and driving conditions, but typically range from 18 mpg city to 25 mpg highway for the VQ35DE and 19 mpg city to 26 mpg highway for the VQ35HR.

Keeping Your G35 Engine Running Strong: Essential Maintenance and Potential Upgrades

Following up on the importance of oil changes, here’s a more comprehensive look at G35 engine maintenance and potential upgrade options:

• Air Filter Replacement: A clean air filter ensures the engine receives a clean air supply, promoting efficient combustion and power output. Replace the air filter according to the manufacturer’s recommendations, typically every 12,000 to 15,000 miles.
• Spark Plugs: Worn spark plugs can hinder performance and fuel economy. Replace the spark plugs following the recommended service intervals in your owner’s manual.
• Coolant System Flush and Refill: The coolant system plays a vital role in regulating engine temperature. A coolant flush and refill at specified intervals helps maintain optimal cooling efficiency.
• Transmission Fluid Service: For smooth gear changes and transmission longevity, consider regular transmission fluid service according to the manufacturer’s recommendations.

In addition to these routine maintenance procedures, some G35 owners may consider performance upgrades to extract a bit more power from their engines. It’s important to note that modifications can impact emissions and may not be legal for street use in all regions. Always consult with a qualified mechanic before undertaking any performance modifications:

• Intake/Exhaust Upgrades: Upgrading the air intake system and exhaust system can improve airflow and allow the engine to breathe more freely, potentially resulting in modest power gains.
• Performance Camshafts: Installing more aggressive camshafts can alter the valve timing profile, increasing power output at the expense of some low-end torque. Carefully consider the trade-offs and ensure proper tuning after such modifications.

• ECU Tuning: Professional ECU tuning can optimize engine performance by adjusting parameters within the engine control unit. This should only be done by experienced tuners to ensure safe and reliable operation.

Remember, prioritizing preventative maintenance is key to ensuring the longevity and optimal performance of your G35 engine. Following a consistent maintenance routine and addressing any potential issues promptly will help you get the most out of this robust powerplant.

Finding Your Perfect G35: Considerations Before You Buy

If you’re considering purchasing an Infiniti G35, here are some factors to keep in mind:

• Model Year and Engine Option: Decide if the earlier VQ35DE or the later VQ35HR engine better suits your needs. The VQ35HR offers more power but may come at a slightly higher price point.
• Mileage and Condition: As with any used car purchase, a thorough inspection by a qualified mechanic is crucial. Look for a car with a well-documented service history and ensure it has been maintained properly.
• Modifications: Some G35s may have undergone modifications. While some mods can enhance performance, others may have been done improperly or compromise reliability. Be sure to understand the extent of any modifications and have a mechanic assess their quality.
• Test Drive: Take the G35 for a test drive to experience the engine’s performance firsthand. Pay attention to power delivery, handling characteristics, and any warning signs.

Unleash the Potential: Owning a G35 with the Renowned Engine

The Infiniti G35 engine stands out for its blend of power, refinement, and durability. It delivers an exhilarating driving experience while remaining practical for everyday use. Whether you’re a seasoned enthusiast or a new admirer of the G35, understanding the engine’s intricacies, proper maintenance practices, and potential upgrade options empowers you to get the most out of this exceptional powerplant.