I have an A trim on my car with shows about 6 PSI at 5700 rpms. (2.87) top pully. So I purchased a 2.62 inch size thinking I should get the boost up to around 8 PSI. After I get it (today) I start reading the posts on getting more boost via pully size and I see most people use a 7 inch Crank pully (I have a 6 inch ) with a larger top pully then the one I purchased. I'm I going to end up with nothing but a Belt that slips? Next time I read the posts before I buy anything. Thanks for any input.