Ok i screwed something up. I used the conversion constant that i got with the directions that i got off this site and its wrong. My speedo is at least 10mph to high now. It was set at 9.04 which is for a 235 tire. I set it at 8.04 which was what the paper said was correct for a 35" tall tire. The speedo is way off but it seams to be shifting great. Also the speedo seams to jump around between 60 and 70 mph. On the highway its off by 1/10 of a mile to high. Which number shoud i use or where can i get it. I atill have 5 changes left.

Please help!

 

Did you find out the revs per mile of your tire? Did the needle jump between 60-70 before you changed the constant?

 

no it didnt jump before. i got the revs from the same paper the directions were on.

 

i think i got it . i was using the number for a 35 12.5 15 tire not a 16