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
Sure. The vehicle will under report speed and driven mileage with larger wheels and tires, and over report both with smaller wheels than tires. I’m not if it’s possible to adjust the speedometer and odometer, or if people even bother.
No, they are calibrated and have technicians that set them professionally.