When you say it wont hold boost. What exactly do you mean? Is it leaking air from a rubber coupling? Does it run perfect and pull hard to the 4000rpm point?Hey guys, so I just installed the Alpha turbo and earlier today everything was running fine. Now, on my way home from work it won't hold boost past 4000rpm. It sputters and pops after 4000. My first thought is boost or vacuum leak. Any suggestions?