A few weeks ago I developed a small exhaust leak at the flex section in my down pipe that gradually got worse. Since I took my mbc out my boost has always been solid at 9psi and would never creep. Today I noticed it going above 10psi. I punched it in second while watching the boost gauge and ended up hitting 18psi at redline in second gear. No wonder my car has felt faster the past couple of weeks.

I get that too. I have the turbo xs mbc. In 1st and sometimes 2nd I'd hit about 15psi, but 3-5th at wot around 4-5k I'd get about 8psi. Not sure what the deal is.