The problem with that carb is that if you lean out the primary to get a good cruise mixture, you will lean out wot. That could be good or bad. The lack of secondary metering blocks means you change a metering plate in the secondary, not as cheap as simple jets. I don't know how holley sized the pvcr on the 3310, but that is another option to get both cruise mixture and wot mixture right. The bottom line IMO is to upgrade to a secondary metering block so you can better tune part throttle as well as wot. I hate to sound like a broken record, but get a book on modifying holleys. Knowledge is power. You can find it on the web, but I find it easier to get it from a book. I have this one. http://www.amazon.com/exec/obidos/t...104-5906991-1252762?v=glance&s=books&n=507846