A very common modification in the LS1 world is porting of the stock mass airflow sensor. Jim Pace Performance Parts has one-upped this practice with their line of Velocity Volume recalibrated 85mm MAFs. These MAFs can be ordered pre-calibrated for several different injector sizes. This allows you to upgrade injectors without a costly PCM re-flash. This one is calibrated for the 30-lb/hr SVO injectors in use on the engine.