Who knows tire sizes

[Rolm]

My intrigue's standard tires are 225-60-16, I can buy a set of almost new tires in this size 215-60-16. Question? will this size of tire mess-up my speedo

[maxwedge]

Too small and yes, you will be going slightly slower than the indicated speed.

[BNaylor]

Originally Posted by maxwedge

Too small and yes, you will be going slightly slower than the indicated speed.

Right on Shep. According to my tire calculator when speedo reads 65 mph actual speed will be 63.85 mph.

[panzer dragoon]

How does a change in width change a tire's diameter (speed)?

[BNaylor]

Originally Posted by panzer dragoon

How does a change in width change a tire's diameter (speed)?

That is because tire manufacturers follow an industry manufacturing standard. According to those standards the specs (see below) on a 215/60-16 tire is different compared to the 225/60-R16 tire. It is not just the difference in width.

------------------ 225---215----Difference

Sidewall height---- 5.31--5.08---(-.23)
Section width----- 8.86--8.46---(-.40)
Overall diam.------26.63--26.16--(-.47)
Circumference---- 83.66--82.18--(-.1.48)
Revs per mile-----781.07-795.11--(14.04)

Therefore, speedo reading 65 mph - actual speed is 63.85 mph.

[Rolm]

Thank you for the info it was very informative. By looking at the numbers it appears very little difference I do very little hwy driving so I think I will buy the tires They are BF Goodrich Traction control Tires almost new and I can pick them-up for a song. Thanks again