right, the purpose is to port match the gasket ends of the intake to head. It is better to leave a little material on the intake making the hole smaller than the head than to get it exact and after bolting it on have a step down as the air goes into the head. Plus it helps with reversion to leave a small step (within 1/16th) on the intake with longer duration cams. Whatever you do be careful or you will have to either get another intake or epoxy the mess ups and try again. Either way it's always fun the first few times port matching.
95 E34 530I V2.37
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