93 civic sedan sohc zc with a t3t4 ar57 trim sport Turbo with cx Mani and a xs power wg . Running 450cc injectors base mapped on crome was boosting 5psi but now only boosting 2psi Max checked all couplers and clamps no holes clamps tight all bolts tight bov is working properly ??any ideas I'm new to this site.

 

check for vacuum leak first

 

check for exhaust restrictions like a melted cat or exhaust manifold leaks like a cracked manifold or blown out manifold seal.