This is very interesting I'm glad you're willing to use yourself as a guinea pig and see if it works. No reason why it wouldn't unless these manifolds are closed up internally aswell. This brings back the idea I had months ago of getting a single stage 328i manifold and cutting the holes for the disas and putting two in and seeing if it would work but it isn't too worth it given how cheap a bare 3 stage is, only for personal satisfaction
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