speedometer recalibration? UPDATE!

[asdiluzio]

If you take a look in this section there is a thread asking about possible speedometer recalibration due to change in wheel/tire size.

I went from a 265/70-16 to a 275/70-17... its only about a 2" jump in size and by using the tire size calculator link above it said I would be moving approx 4.7MPH faster than what the speedometer says.

Here is the kicker... As I drove by a WORK ZONE on the turnpike there were the speed detectors to show you your speed, I guess to keep people from speeding, and my speedometer was dead on.

Any thoughts on this?

 

[Cleric]

If you are talking about the "tire size calculator," it states that it is speed dependant. It is actually based on a percentage. The speed that you would have to be going to see this change is 60mph. You said that you were in a construcion zone...were you going slowly? There are several factors that go into this calculation, so even @ 60mph it will probably vary from the 4.7mph variance listed.

 

[asdiluzio]

Well it was late at night and I was doing 60MPH. I even went back and went faster at 65MPH and I was still dead on.

 

[Colemanfu]

I love those things - it makes driving like a video game! What 's your high score? You get extra points if it flashes red.

They have acutaly had those detectors stolen in our county and now have to lock them down to trees or attach them to trucks. I saw one with a boot on it. What do you think they do with those things when they take them?