I have about a year on a Rebuilt set of Injectors with Monark Nozzles.
About 6 or so Months ago I finally got around to Drip Timing my IP and set it at aroximately 28 degrees BTDC.
I ended up with undesirable Nailing.
I had to retard the timing some to reduce the Nailing.

Up until I advanced the Timing I did not think advancing the timing could cause Nailing. I thought it was only Late Timing that did that.
I guess you have to find the "sweet spot" for each vehicle when it comes to timing.

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84 300D, 82 Volvo 244Gl Diesel