Guys my evo 8 is pretty much stock, it was a bank repo, so I had to get it back to stock, before I even thought about modifying it, the issue I'm having is I installed a boost gauge and a turboXs manual boost controller, I want stock boost and ill be happy, when I climb to higher rpms the car really breaks up and misfires, sometimes my charge pipe to the throttle body blows off, I made a couple passes and I'm around 15psi, my cat is also bad I have it fauled out to pass inspection, like I said if I climb to higher rpms it really spits/sputters and misfires, but when just driving point A to B no problems, I was told coils first then test pipe. Any other suggestions would help thanks guys!

 

Have a look at your plugs, change them and gap to .022 and see what happens--, yes new plugs first.