I put on shorter tires because they were available and free but that throws my speedo off. I got to looking for an answer and here is the formula I used tell me if it makes sense.
stock short
225/60/16 225/50/16
rev per mile 781.3 837.0
vss pulse 23430 25100
per mile
variable 29.98
does that make logical sense or not? it does to me, I just wanna get the speedo as close to right as possible