Hello All, this is my first post! The 1985 300 OM 617.952 motor had 125 hp. The first series of this motor, introduced in the 1978 300SD had 120 hp. Then installed in the 1981 300TDT, it made 123 hp. Finally in 1985, specs were increased to 125 hp.

I believe minor modifications were made to the throttle lickage, valve head, vacume lines/pumps and injection pump. The biggest change in 1985 was the ability for the Transmission to downshift to 1st from 2nd gear while moving. Some other tweaks are possible, but these are basic changes to my knowledge.

Glad to be a new member on the post!