Hello all. I replaced my 250 Pro XS cowl with a CDR Alien cowl. I was looking at the stock plenum that came off the motor under the stock cowl. I noticed it had what looked like a vacuum port that went to the 2,4,6 cylinder head.

The CDR cowl doesn't have this and there is just a 3/4" barb fitting sticking up on that head. What is that? Do I need to address it? Thank yall