a cars speedo is designed to show slightly slower. Many facter change. Tire size depending if worn or not extra extra. they call it safe and give little allowance.
Same with a speed camera. If you get a fine for say 61km/h in a 60km/h zone. you would have done around 63-64 past it.
yuo have this the wrong way around.
A stock car's speedo overstates your speed to avoid having potential lawsuits on their hands
speed cameras generally give u a little allowance though.. As you've stated.
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