How Much Hp Does A Camshaft Add

How Much Horsepower Does a Camshaft Add?

Adding a performance camshaft is a popular modification for boosting horsepower and torque in internal combustion engines. But the question many enthusiasts ask is: exactly how much horsepower does a camshaft add? The answer, unfortunately, isn't a simple number. The horsepower gain from a camshaft upgrade depends heavily on several factors.

Factors Affecting Horsepower Gains from a Camshaft

Several interconnected variables determine the actual horsepower increase you'll see after installing a new camshaft. Let's explore the key players:

1. The Engine Itself

The base engine significantly influences the outcome. A naturally aspirated four-cylinder will respond differently than a supercharged V8. Larger displacement engines generally show greater horsepower gains than smaller engines because there's more potential for increased airflow.

2. Camshaft Specifications

The camshaft's specifications are crucial. These include:

• Duration: This refers to how long the valves stay open. Longer duration cams allow for more airflow, potentially increasing horsepower at higher RPMs, but can reduce low-end torque.
• Lift: This is the distance the valves lift from their seats. More lift means more airflow, leading to potential horsepower gains but, again, potentially sacrificing low-end torque.
• Lobe Separation Angle (LSA): This determines the overlap between the intake and exhaust valve timing. Different LSAs can affect power delivery across the RPM range. A tighter LSA generally improves low-end torque while a wider LSA often favors high-end power.

The camshaft's design for a specific application is critical. A cam designed for high RPM performance on a race car will not necessarily offer the same benefit on a street car.

3. Supporting Modifications

The effectiveness of a camshaft upgrade is significantly impacted by other modifications. If you're only upgrading the camshaft and leaving other components stock, the potential gains will be limited. Consider these supporting modifications:

• Headers and Exhaust: A restrictive exhaust system will bottleneck the increased airflow from the cam, limiting horsepower gains. Upgrading to a free-flowing exhaust is highly recommended.
• Intake System: Similarly, an inadequate intake system can restrict airflow. Improvements here can unlock the cam's full potential.
• Fuel System: The fuel system must be able to supply enough fuel to support the increased airflow from the larger cam. Insufficient fuel delivery will hinder performance gains.
• ECU Tuning: The engine's computer (ECU) needs to be tuned to match the new camshaft's specifications. Otherwise, the engine may run poorly or even damage itself. This is absolutely crucial.

4. Measurement Methods

Even with the same engine and camshaft, different dynamometers can provide slightly different horsepower readings. The environment (temperature, humidity) can also affect results.

Realistic Expectations

Instead of focusing on a specific horsepower number, it's more realistic to anticipate a percentage increase. You might see gains in the range of 10-30%, but this is highly variable based on the factors mentioned above. In some cases, you might see less, and in others, significantly more.

Conclusion

The horsepower increase from a camshaft is not a fixed value. To maximize the potential of a camshaft upgrade, it’s vital to consider the engine, camshaft specifications, and supporting modifications. A holistic approach, including professional tuning, will yield the best results and ensure a reliable and powerful engine. Remember to always consult with experienced mechanics and tuners for advice tailored to your specific vehicle and goals.