First thing I would do is check the timing chain for stretch. This is done at the cam sprocket and harmonic balancer comparisons. If it's off a couple of degrees then you should install a woodruff key that compensates. I would advance the cam a couple of degrees to bring up the low end torque. Which means the car will have more power down low.
The woodruff keys are available at ******** az.
Next thing would be to advance the injection pump 3 degrees over stock. The timing is probably late due to timing chain stretch. Hopefully you'll have enough of an adjustment. Otherwise you'll have to remove the injection pump and reposition to obtain the correct timing. I had to do this on my 300sd. Like I said makes a big difference in performance.
Lastly put a manual boost controller set to 15 psi. The factory setting is probably off by a couple of psi. You'll needs a boost gage to monitor the upper level of boost, these are fairly cheap on eBay. Also the manual boost controller is also available on eBay fairly cheap.
All these improvements make a big difference.
You'll be very happy when these adjustments are made.
Got to love these old mechanical diesels.
Roddy

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