Comment on the loudness. Some have reported this after installing new Injectors and fournd the sound decreased after 200 or so miles.

Also the Fuel Injection Pump timing can have an effect on loudness of the Injectors.

Retarded IP Timing will cause "Nailing" and I also found out that advancing the timing will also cause Nailing.

The Retarded Fuel Injection Pump Timing can be caused be Timing Chain Stretch.

I do not know if on you 87 the Timing Chain stretch can be corrected with an Offset Woodruff Key or not. But, even if the Chain stretch is not corrected the Fuel Injection Pump can be re-timed. But, checking/diong both would be better.

__________________
84 300D, 82 Volvo 244Gl Diesel