Engine intake runner length refers to the distance between the engine intake valve and the point where the air and fuel mixture enters the intake manifold. It is an important factor in determining the performance and efficiency of an engine.
The length of the intake runner affects the velocity and pressure of the air and fuel mixture entering the engine. A longer runner length allows for more time for the air and fuel to mix, resulting in increased torque at lower RPMs. A shorter runner length allows for quicker airflow, resulting in higher RPM power.
Yes, intake runner length can be adjusted through the use of variable-length intake manifolds. These manifolds have adjustable flaps or valves that can change the length of the runners based on engine speed and load.
A longer intake runner length can improve low-end torque, resulting in better acceleration and drivability. It can also improve fuel economy by allowing for a more complete combustion of the air and fuel mixture.
While a longer intake runner length can provide benefits in low-end torque and fuel economy, it can also limit the engine's high-end power and performance. This is because a longer runner length slows down the airflow, resulting in less air and fuel entering the engine at higher RPMs.