Edelbrocks have an issue. In an effort to ease installation they use a mid-flange set-up that has all five tubes going to one-half of the mid-flange and all five continuing after the mid-flange. Problem is that with five tubes exerting different twisting forces on their respective flanges, and given the high heat, the mid flanges warp and will no longer hold a gasket. My car had Edelbrocks on it when I got it and over the eight inch or so distance of each mid flange they were warped around a sixteenth of an inch! Even more in some spots. Once this happens you should be able to grind the flanges flat and be confident they will stay put since the already moved, but the process is a PITA.