How would My 93 rx7 react if I had a boost leak?
 

My car falls on its face bad between 3 to 5 lbs of boost depending on how high the rpm's are if the rpm's are higher it will start stuttering really bad around 2 to 4 lbs of boost or just fall on its face completly. could this be a boost leak? or any other ideas?

yup, you might have a loose vacuum hose or maybe one of the intercooler hoses are loose. I have the same problem right now and going to redu the vacuum lines i messed with when i swapped my twins. I didn't have this problem before I swapped it. Good luck!