Due to some debate on another thread, my interest became piqued when thinking about a low rpm Torque type engine. My self professed belief is that the only way you can increase the power available from an engine operating at rpms below 5252, is by increasing torque which will then calculate out into more horsepower. This thread is not about that or rekindling that debate. One of the posters had mentioned that manufacturers control the operating characteristics of an engine by changing camshaft profiles. A manufacturer can take a basic engine and define its probable use by altering the lobe shapes and relationships. Basically an engine can be designed to produce low end power or high end power.
After thinking about it a little, I began to wonder more about how this actually works. The key point here is producing more power while maintaining the same RPM. I realize that increasing displacement will automatically allow more power at the same rpm. I also think that increasing the compression ratio can provide more power at the same rpm. But I began to think about the camshaft thing. Changing the camshaft will allow more air to enter the engine and require more fuel in order to have the proper fuel/air ratio. When you increase the air entering the engine, the rpm will then increase also. Now I thought I knew the answer, but the more I reflected on it, the more I wondered. I know that camshafts can be optimized and will produce more power at the same rpm, but without altering displacement or compression ratio, or increasing the rpm, how does it do it ? I'm thinking more complete combustion at the same rpm, but I'd like some on topic opinions.
After thinking about it a little, I began to wonder more about how this actually works. The key point here is producing more power while maintaining the same RPM. I realize that increasing displacement will automatically allow more power at the same rpm. I also think that increasing the compression ratio can provide more power at the same rpm. But I began to think about the camshaft thing. Changing the camshaft will allow more air to enter the engine and require more fuel in order to have the proper fuel/air ratio. When you increase the air entering the engine, the rpm will then increase also. Now I thought I knew the answer, but the more I reflected on it, the more I wondered. I know that camshafts can be optimized and will produce more power at the same rpm, but without altering displacement or compression ratio, or increasing the rpm, how does it do it ? I'm thinking more complete combustion at the same rpm, but I'd like some on topic opinions.
