Originally Posted by Dustin@Z1

Based on our dyno tuning we agree with what Specialty Z states IF combined with Test Pipes and Exhaust. The combo of all three (including the Stillen Gen 3) does lean out the car significantly.

A Stillen Gen III Intake by itself, without any other mods, will not lean out the car enough to be of any concern. It is only when you combine the intake with other supporting mods that when a Lean condition really becomes apparent and a tune is required.