Hi Rogelio-Durant did offer a "speed set" of gears with a ration of 3:90 as an option in 1929 for cars running on flat surfaces like the central part of the US. I have a set which I built up in a complete rear end but then had second thoughts. One-if you go faster, then the mechanical brakes/narrow tires become more critical for stopping. Two-any increase in speed must be associated with a corresponding increase in horsepower. In the end, I decided 35-40 MPH will work just fine. For what it's worth. Phil

Where Are You From? Portland

Do You own a car built by Durant? 1929 Model 60

Dear Phil, I am sorry I didn´t see your answer before. It looks like a 3:90 is a good choice in my case. I have a lighter car, speedster, and Iive in flat surface area. However, I have to pay a good price to manufacture the new gears. I will think if it is worthwhile. Thanks!

Where Are You From? Argentina

Do You own a car built by Durant? yes