The previous owners of my car appear to have put the wrong size tire on, is there a way to tell if the speedometer is calibrated correctly to these tires or if its calibrated to stock?

I am considering getting new tires and I want to see if I want to go with the same size tires or the stock size tires.

 

Yes - here is the link
http://www.csgnetwork.com/tiresizescalc.html

When I put new alloy wheels and tires on my 09 Camry LE, I converted from stock 215R6016 to the same size as the SE 215R5517. That calculator program let me know the circumference difference was less than 1%.

 

I figured it was a difference in circumference of just over and inch, anyone know what difference, if much of any that will have on the speedometer?

 

Based on my car's standard tire with a circumference of 82 inches and assuming the new tires increased the circumference by 1 inch:

1/82 = 1.2%

So if your new circumference is 1.2% greater, the impact on your speedometer would depend on your speed and be under by 1.2% - so at 30 mph, you are really going 0.36 mph faster at 60 mph 0.72 mph faster and at 90 it would be about about 1 mph. In 100 miles on the odometer, you would be traveling 101.2 miles.

In other words, difference is negligible.

Hey bro, were you snoozing in Algebra class ?

 

Haha actually I am pretty kick *** at math, i just didnt feel like going through it so i figured someone would and it looks like i was right, thanks for that btw