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The Pontiac 455 is a powerhouse of an engine, known for its impressive torque and performance. For enthusiasts looking to enhance their engine’s capabilities, upgrading the camshaft is one of the most effective modifications. In this article, we will explore the best camshaft upgrades for the Pontiac 455, focusing on the Comp Cams 270H and 280H camshafts, and the power gains they can provide.
Understanding Camshaft Specifications
Before diving into the specific camshaft options, it’s essential to understand the key specifications that influence engine performance:
- Lift: The distance the valve is opened, affecting airflow.
- Duration: The amount of time the valve is open during the engine cycle.
- Overlap: The period when both intake and exhaust valves are open, impacting performance at different RPMs.
Comp Cams 270H Camshaft Overview
The Comp Cams 270H camshaft is a popular choice among Pontiac 455 enthusiasts. Its specifications are designed to provide a balance of street performance and power.
Specifications
- Lift: .470” intake / .470” exhaust
- Duration at .050”: 230° intake / 236° exhaust
- LSA: 110°
Power Gains
Upgrading to the Comp Cams 270H can yield significant power gains, particularly in the mid-range RPMs. Users have reported improvements in both horsepower and torque, making it a solid choice for street applications.
Driving Characteristics
With the 270H camshaft, drivers can expect a noticeable increase in throttle response and overall engine performance. The cam is designed to work well with factory components, ensuring compatibility and reliability.
Comp Cams 280H Camshaft Overview
The Comp Cams 280H camshaft offers a more aggressive profile, making it ideal for those seeking maximum performance from their Pontiac 455.
Specifications
- Lift: .480” intake / .480” exhaust
- Duration at .050”: 236° intake / 242° exhaust
- LSA: 110°
Power Gains
The 280H camshaft is designed for high-performance applications, providing increased horsepower and torque across a broader RPM range. Many users have reported substantial gains, particularly at higher RPMs, making it a favorite among racers.
Driving Characteristics
While the 280H camshaft offers excellent performance, it may require additional modifications to the engine for optimal results. Drivers can expect a more aggressive idle and increased responsiveness, making it suitable for performance-oriented builds.
Comparing the 270H and 280H Camshafts
When choosing between the Comp Cams 270H and 280H camshafts, consider the following factors:
- Intended Use: The 270H is better for street use, while the 280H excels in performance applications.
- Power Band: The 270H provides better mid-range torque, whereas the 280H shines at higher RPMs.
- Idle Characteristics: The 270H has a milder idle compared to the more aggressive 280H.
Installation Considerations
Installing a new camshaft requires careful consideration and planning. Here are some important factors to keep in mind:
- Supporting Mods: Consider upgrading the carburetor, intake manifold, and exhaust system for optimal performance.
- Valve Springs: Ensure that your valve springs are compatible with the new camshaft specifications.
- Tuning: A proper tune is essential to maximize the benefits of your camshaft upgrade.
Conclusion
Upgrading the camshaft in a Pontiac 455 can lead to significant improvements in performance and driving experience. Both the Comp Cams 270H and 280H offer unique advantages, catering to different driving styles and preferences. By carefully considering your needs and making the appropriate modifications, you can unlock the full potential of your Pontiac 455 engine.