Re: overdrive help
The lower drop in rpm (36%) usually works better with the shorter ratio rear axles like 4.11:1 or 4.27:1 when a car is already equipped that way. If you have a 3.78:1 or taller gear set then the lesser 26% rpm drop would likely be a better fit. The drop in rpm is more like the drop in rpm between 2nd and 3rd gears. This blends the ratios better for overall use and still gives a decent rpm at modern highway speeds. 3.78:1 may go either way OK but 3.54:1 not so much.
|