speedo gear...yeah yeah yeah...its diff ?

[Paully's5.0]

Did the aod - t5 swap, and I don't know what gear is in the tranny, and I may have 3.55's in the rear (previous owner said it was done by the previous owner)

Anyway I took a stab and got the 20 tooth gear....and when it say's I'm doing 55, I'm really doing 65.

So the question...do more teeth make the speedo read slower or faster?

I checked out this site

http://www.geocities.com/mgnedell/notchback/tech/speedo.html

cuz if I do have 3.55's, then I'll have to go with the 23 tooth (cuz I already have the 20)

Otherwise I have the 3.27 orignial gears and I'll either have to go with the 19 or 21 tooth.

Just trying to figure this out!

 

[5.0 Nostalgia]

First find out what gears you have. If you speedometer is reading slower than your actual speed, you actually need to back off on the speedometer gear. You probably don't have 3.55s. My 23 tooth reads pretty accurate with the 3.55s.