What's making you think it's bad? Borrow a vacuum pump & see if it will hold vacuum. All of em I've ever seen, the slope starting point is adjustable with the 3/32" allen wrench & you can solder strips of feeler gauge on the back side on the pod on either side of the notched arm to limit the arms' travel into the pod to limit the total if need be. Yes NAPA will have a selection & a can with 8 on the arm might be a good choice but one with more ain't a problem if you are willing to tune it with the strips.