Size does matter. With a larger, lower-backpressure, quicker-reacting turbine and a better-suited wastegate actuator, boost comes on faster and stays longer. The Banks Quick-Turbo turbine housing is shown here with the BigHead actuator installed. Compared to the standard T3-style actuator, the Banks unit has twice the diaphragm area and a spring that's twice as stiff. The result? Less wasted boost.