Saw a truck around town today with a ridiculous lift kit and chunky off-road tires that were clearly much larger than factory standard, and it got me thinking; if you install this kind of modification in a car, do you need to adjust the speedometer to compensate? What about the odometer?
My logic is the only absolute measurement the car has is how fast the wheels and drive shaft are turning, so presumably there is some sort of multiplier - 1 revolution = X meters - that is then used to show speed and track distance travelled, but that factor would need to change if the circumference of the tires did
I had to when I changed the tyres on my ebike. The slick tyres were smaller diameter than the chunky off road fat tyres I had on there, and I had to tell it the new diameter so that it could correctly determine my speed.
You can also tell it the wrong diameter to increase top speed.