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BMW E46 330d (M57D30) swirl flap removal - pros and cons

Posted: Tue Oct 01, 2024 11:41 am

by spinecki

BMW E46 330d (M57D30) swirl flap removal - pros and cons

Pros of removal:

Eliminates risk of flap failure and engine damage
Potential for improved engine performance
Reduced maintenance in the long run

Cons of removal:

May affect low-end torque
Could impact emissions and potentially fail inspections
Might require ECU remapping for optimal performance

Removal process overview:

Remove intake manifold
Carefully remove swirl flaps and associated mechanisms
Install blank-off plates or a modified intake manifold
Optionally, remap ECU to optimize for removal
Reinstall intake manifold and test

Note: Swirl flap removal is a popular modification but may have legal implications. Check local regulations before proceeding.