Ok, so I put 3.73s in my car and got a Diablo Predator to fix the speedo. At 68 mph, it was reading 80 mph. I also have 295/35/18 on back so I wanted to adjust for that. After adjusting the computer for the gear, I put rev per mile at 772 for the rear tire. At 32 mph my speedo was still reading 35, not a huge deal but by 70 it would be well off. So to try and correct I dropped the rev per mile to 725, thinking this would slow the speedo down more, well it didnt. Now at 30 mph it is reading 35. I am going to bump it up to 796 rev per mile as some of the calculators give that for my tire size, but im thinking this is not going to help it. Any help or info would be appreciated.
