When a car is run at part throttle, this interruption in the airflow causes excess vacuum, which causes the engine to use up valuable energy acting as a vacuum pump. (en.wikipedia.org)
Under part throttle, the inline - six proves as smooth and refined as ever. (automobilemag.com)
That twin - turbo V8 engine is a cracker, though, even if the turbines hit a bit too hard and somewhat artificially in certain part throttle applications. (automobilemag.com)