ISR Long Tube Headers for the Infiniti G37: A Comprehensive Guide
The Infiniti G37, known for its powerful VQ engine, is a popular platform for aftermarket modifications. One of the most sought-after upgrades is a set of long tube headers, and Injen Supercharger Racing (ISR) is a prominent manufacturer in this space. This guide delves into ISR long tube headers specifically for the G37, exploring their benefits, potential drawbacks, and considerations before installation.
What are ISR Long Tube Headers?
ISR long tube headers are a performance upgrade that replaces the factory exhaust manifolds. Unlike shorty headers, which maintain a relatively similar design to the stock manifolds, long tube headers feature significantly longer primary tubes. This extended length allows for improved scavenging—the efficient expulsion of exhaust gases—resulting in increased engine power and torque. ISR designs these headers for optimal flow and to minimize exhaust restrictions, maximizing the engine's potential.
What are the Benefits of ISR Long Tube Headers on a G37?
The primary benefit of installing ISR long tube headers on your G37 is a noticeable horsepower and torque increase, particularly in the mid-to-upper RPM range. This improvement stems from the enhanced exhaust scavenging mentioned earlier. Beyond raw power gains, you'll also experience:
- Improved throttle response: The engine reacts more quickly and decisively to throttle inputs, enhancing the driving experience.
- Enhanced exhaust note: Long tube headers typically produce a more aggressive and sportier exhaust sound.
- Increased engine efficiency: By improving exhaust flow, the engine can breathe more efficiently, leading to better fuel economy (though this improvement might be marginal).
What are the Potential Drawbacks of ISR Long Tube Headers?
While the benefits are significant, it's crucial to acknowledge potential drawbacks:
- Increased drone at cruising speeds: The improved exhaust flow can lead to a noticeable drone or humming sound inside the cabin at certain RPMs. This is a common complaint with long tube headers.
- Potential for check engine light: Depending on the specific design and your vehicle's setup, you might trigger a check engine light due to changes in the exhaust system's oxygen sensor readings. An aftermarket tune can often address this.
- Installation complexity: Installing long tube headers usually requires more time and expertise compared to other bolt-on modifications. Professional installation is often recommended.
- Cost: Long tube headers are a relatively expensive modification.
Do ISR Long Tube Headers Require a Tune?
While technically not strictly required, tuning your G37's ECU (Engine Control Unit) after installing ISR long tube headers is highly recommended. This is because the increased exhaust flow changes the engine's air/fuel ratio and timing parameters. A tune optimizes these parameters, maximizing the performance gains from the headers and preventing potential issues like running lean, which could damage the engine.
How Much Horsepower Can I Expect to Gain with ISR Long Tube Headers?
The actual horsepower gains vary depending on several factors, including the specific G37 model (Coupe vs. Sedan, year), other modifications (intake, exhaust, etc.), and the quality of the installation and tuning. However, you can typically expect a gain in the range of 15-25 horsepower, alongside a similar increase in torque. This is just an estimate, and individual results may vary.
Are ISR Long Tube Headers Street Legal?
The legality of aftermarket headers, including ISR long tube headers, varies by region and local emission regulations. Some areas may have stricter rules regarding modifications to the exhaust system. Check with your local authorities to ensure compliance before installing.
What are the Best Long Tube Headers for a G37?
While ISR is a reputable manufacturer, the "best" long tube header is subjective and depends on your priorities (power gains vs. sound, cost, etc.). Researching different brands and reading reviews can help you determine the optimal choice for your specific needs and budget. Factors like material (stainless steel vs. coated steel), primary tube diameter, and collector design all contribute to the performance characteristics.
This comprehensive guide provides a solid foundation for understanding ISR long tube headers for the G37. Remember to always conduct thorough research, consult with experienced mechanics, and prioritize safety when undertaking any performance modifications to your vehicle.
