Vehicle speed sensor

This is getting more confusing, I originally thought it was going to be a simple project with just a few lines of code but its going way over my head.

I dont really need much accuracy, just at 60hz input I want any output thats over 100mph.

I looked at the hall sensor file but I wouldn't know how to adapt that to my project.

I appreciate your help guys and if I can get this working I will happily contribute to someones beer fund.