noquarter - good progress! I've got a complete exhaust system for your car, if you want a put it all correct again. Came off a sedan with 143k miles, totaled after a major collision.

Replace the air filter, and then check the boost again. You may need to adjust the waste gate to get up to 12-13 psi. No need to go any higher, you'll just be making the intake charge hotter than needed at that point, and will start loosing power without more fuel or some type of cooling of the compressed air. Check the ALDA to see if it is holding pressure or leaking.

After that, fine tuning until you can get back to 12 sec or less.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC