speedo problems

[shaun89]

my 89 k5 originally had 3.08s and 31" tires but now i have 3.73s and 38" tires (im regearing with the $600 uncle sams giving us) but i cant find a site that has a calculator to see my correct speedo speed. so with a speedo gear for 3.08s , 3.73s in my diffs and 38" tires, does anyone how off my speedo really is? sorry for being a pain guys.

 

[4X4HIGH]

Your speedo should be really close to being accurate. With 3.08's and 31" tires your RPM's would be 1519 at 65mph in OD and with 3.73's and 38" tires your RPM's would be 1498 at 65mph in OD.

 

[Mudstud]

Your speedo should be really close to being accurate. With 3.08's and 31" tires your RPM's would be 1519 at 65mph in OD and with 3.73's and 38" tires your RPM's would be 1498 at 65mph in OD.

Ain't we got some fart smellers on this board?

 

[shaun89]

awesome, i would have never thought to check the rpm difference, thanks