boost leak? or tighten ze wastegate?
 

so I start to boost around 3200ish when WOT... dont really go into boost unless i step on it pretty hard not WOT but least 50-70% down. I get to like 4psi by like 4200-4300 and then at 5k it gets to 5.5 and pulls like a bat out of hell. I have the insanly long and cheap jim pipes with the sab 900 so i know i loose some pressure there. I got a second wastegate because my stock one came fucked so i had to wait like 3 months for GReddy to send me a new one. Is the new one a bit to loose so the wastegate is a bit open and thats why it takes so long or should i just throw in a home depo style MBC. If it is the wastegate how the hell hard should i tighten it down and all that jazz? Or do i have bigger problems like a leak in a coupler or like at the manifold. My vac reads 19-20 on idle and during shifts like 20-22ish.

check your turbo to the manifold gasket when mine blew out it did this as well

Use a 2ft length of vacuum line. Insert one end in your ear and they use the other to probe around the exhaust manifold, turbo flange ... etc. Listen for a putt putt putt putt noise, it'll be obvious. If you hear this, you've got an exhaust leak.

Just make sure you do this in privacy, people will think you've lost it if they see you doing it. :)

where would i get a new one of these?

well mine came from the mitsu dealer but my turbo is different you could check jgs http://www.jgstools.com/turbo/index2.html or contact the place where you bought the greddy