Okay so my mods are as follows: 3" CAI, LS4 TB, BadMab header, ZZP 3" downpipe catted, Tsudo catback, 3.0" pulley. I was hitting 16.6 psi before, now I can barely hit 9.5 in third gear at full throttle for some reason. I'm also 90% sure that I have a big exhaust leak between the dp and catback, could that be causing a lack of back pressure which results in less boost? Anyone else experience this problem?