So like a month ago i put on a NAPA/Gates 537 8 rib belt on the supercharger side of my car as the 545 I had was only like 20% into the tensioner. After doing so, about a week later I developed a squeal on the blower belt system. Replaced both idlers and the tensioner with Thump Racing units. Still squealing. So I ordered a Dayco 537 belt...no more squeak....I don't know what it is about the gates micro-v belts....put a fan belt on wife's car about a year ago....same thing constantly squealed....so switched it to dayco...no issues...just a piece of advice if you will....watch out for the gates belts.