Hi guys, I thought I'd chime in. I have a 84 & 87 300TD. My 617 gets 25 psi boost above 75 mph and 22 psi for my 87. I installed EGT & Boost gauges as well as vacuum and voltage. I used a fuel hose pincher to completely cut off the air signal to the waste-gate then LEANED the ALDA and adjusted full load limiter linkage to allow more fuel at full load. This combination has given awesome performance on my fully rebuilt 617 with fifty thousand miles of constant hammering(I live in a hilly area). My 603 has 295,000 miles on it and for two years has been running at high boost with no problems. I let them cool down a bit before shut down and high boost uses more oil so don't be surprised. One thing you can do to dramatically improve acceleration on a 82-84 turbo is to find a wrecked 85-95(123 or 124) and remove the torque converter which has a stall speed of 2,300 rpm and replace it with the original which has a stall speed of 1,800 rpm. One thing to note: before increasing boost make sure you have a timing chain which does not have more than a couple degrees of stretch and that the start of delivery is perfectly set. These two factors can cause high EGT's which can cause ring/cylinder damage. Also since you're running high boost you have to keep a close eye on your oil level and change it no later than 3,000 miles(Mercedes recommends 2,500 for turbo diesels) and make sure your cooling system is clean with the right ratio. I have found if you're careful there is no noticeable extra wear and tear from running these engines at high boost. I have seen a number of 617 where the owner enriched the ALDA creating a very smoky situation. These engines always have a shaky idle as there combustion chamber is filled with carbon which increases the compression ratio a little causing the engine to huff. A overly rich setting is going to muck up the engine and dirty the oil. Try to make sure the engine doesn't smoke too much is you must enrich since we don't want to defame the character of our beloved Mercedes diesels by blowing foul black clouds. Good luck!