[danielf]

Can anyone tell me what speedo gear to get now that i will be changing my rear end? I dont understand how to figure out the formula and was hoping someone has already done it or knows how to do it. Heres what ive got if it helps..

C4 A/t
24.6" Tire Hieght
2.80 open 8" rear end

going form 2.80-3.25

[mccance]

try this website it works for most cars. http://www.sccoa.com/faq/speedgr.html your drive gear should be 7 tooth I believe.

[Shnate]

how do you verify the speedos accuracy after it's all done? Just go by a cop at 65 and get a 73 mph speeding ticket? haha just wondering. I might do a gear swap the same as yours.

[mccance]

its pretty simple math really. just drive a measured mile. set your speed at a constant rate. I use 60 mph as that is the easiest to do then the forumula is velocity = distance / time. so basically 3600 (the number of seconds in an hour) divided by how many seconds it takes to travel a mile, at 60 mph it should be 60 seconds. less than 60 seconds you are going over 60 more and you are going less than 60

[danielf]

So i couldnt figure out what gear i needed so i gave Cj Pony Parts a call. They said for my year and trans it was an 8 tooth gear and i would need a 21 tooth speedo gear. So now that its all all taken care of, it will be here Tuesday!