A simplified example of a turbo’s operation is to compare it to an air pump. The turbo is designed to reach peak boost pressure quickly, while creating minimal exhaust backpressure in order to drive the turbine wheel. Performance turbos differ from stock in a number of ways: most have larger housings(which increase air-flow,) larger wastegates(that prevent premature “blow-open”,) and some “ball bearing turbos” replace the bushing with ball bearings providing quicker “spool-up”.