1993 will have the vacuum operated wastegate. Go back and make sure everything is correctly routed and that you haven't unplugged anything electrical going to any of the vacuum transducers or switchover valves. If you don't have vacuum holding the wastegate closed, you have no boost.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]