Originally Posted by DslBnz

A 300SD at 5000 rpm would have a piston speed of 77000 fpm.
A 300SDL at 5000 rpm would have a piston speed of 70000 fpm.

A 300SDL has a stroke that is less than 91% of the OM617.

Thus, at 5450 rpm, the 603 piston speed would match that of an OM617 doing ~5K.

5K in an 603 is like 4550 in an OM617.