* Displacement: This is the volume of the cylinders. 5.7L (or 350 cubic inches) and 383 cubic inches are *displacement* figures. They describe the engine's size in terms of the total volume of its cylinders. They are different sizes.
* Physical Size: This refers to the engine's overall dimensions (length, width, height). Even engines with the same displacement can have different physical sizes due to design differences.
* Horsepower/Torque: This refers to the engine's power output. This varies significantly depending on the engine's design, modifications, and condition. A 383 typically produces more horsepower and torque than a 5.7L, but that's not always the case.
Therefore, you need to be more specific about what kind of "size" you're interested in. If you're asking about displacement, the answer is 5.7L (approximately 350 cubic inches) for one and 383 cubic inches for the other. They are different sizes.
