udp is nice, but exh help has 2 b bar-none, the biggest help 2 this car that most go after. (yes the manifold itself has been a choke, just took the masses a long time 2 figure that 1 out, but 2 any1 that understood it, the stock design left much 2 b desired.) the really good mods r 1s that continue 2 help as u put more on.
you have to look at the hole picture he did it right he put on a intake, tb, and manifold now he no longer has to worry about flow into the engine but next i would recommend a full exhaust header, flex, cat back and then do some head work. make it all flow and you will really grin. oh yeah and while your at it work on your fuel nice high flow feul rail bigger injectors and mass air would just complete the total package. biggest thing to remember is air feul and spark get these all taken care of and your golden your on your way to a great set up can't wait to here about more mods good luck
most people just bore the hole 4 the TB, more aggressive is 2 lob more epoxy on ur runners right b4 they meet the head and thus b able 2 grind out those tumors in the runner just b4 they meet the head.