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DISA Boost Proof Modification
From MS4X Wiki
The DISA valve uses vacuum to switch or close the flap that seperates the two intake manifold halfs. The vacuum source is a small hole located on the inside facing part of the flaps base plate.
Once you add positive pressure aka boost to your engine, the DISA mechanism can get harmed and stop working or worse, leak boost.
There is a way to get around this and this guide shows you how.
