Why do engines with systems like Nissan’s VVEL still use a throttle body?
Posted by cnvrtx3@reddit | askcarguys | View on Reddit | 1 comments
If systems like VVEL (variable valve event and lift) can basically control airflow by adjusting valve lift and timing, why do these engines still have a traditional throttle body?
From what I understand, in theory you could just control engine load entirely through the valves and keep the intake wide open, kind of like what BMW Valvetronic does. So what’s the throttle body still doing there? Is it just a backup? Or does it actually play an active role?
TallComputerDude@reddit
I think I remember reading that it's a backup. It would suck to have a runaway event because you wanted to save a few bucks skipping the throttle.