BHD,
About a month ago, I put a 2.46 into my 300SD. Yesterday, I put a speedometer from a 380SE into my 300SD. Problem solved. No more computations while I am driving the sweetest riding diesel in the world.
That 2.46 is the way to go and I agree about acceleration not being adversely affected. I cannot tell a difference from the 3.07. I know there must be, but it seems negligible. I am now going to start recording fuel mileage numbers. I was getting a steady 28 mpg with the 3.07, it will be interesting to see what I get with the new setup.
Tom