When installing a gasket on the supercharger look very closely at the end where the supercharger snout is. You will see there is very little room for error. My gasket was only on at that point by 1/8 th of an inch even though the bolt holes where lined up and the rest of the gasket matched fine. My car sucked air through there and it sounded like a high pitch wine. It was found with the aid of soapy water and confirmed with carb cleaner. (car bogs when there is a leak) There is room for at least 3/8 of an inch of gasket.
No leak on the new one, knock on wood.
This problem was reported with two different makes of gaskets.
Just wish I would of notice on the first install.
Top picture of a gasket on a new Pontiac gasket.No notch cut out which is good. On the bottom two you can see the lack of contact.