Tires: Wheel size vs width of sidewall, discount tire, bob bob

Question
I have a '96 Toy Tacoma w/14" wheels w/hubcaps and have seen people advertising 15" wheels w/tires for sale. My tire size is p195x75x14 and these on the 15" wheels might be something like p215x70x15. How would a change like this affect the speedometer/odometer?  How do you calculate what tire size would have zero impact on the speedo/odo when going from a 14" wheel to a 15" wheel?

thanks

Bob

Answer
Bob,

Doing this type of change is fairly complex until you've done it a few times.

My suggestion is to work with someone who is familiar with doing this - Tire Rack and Discount Tire are 2 of many who have the expertise.

But as far as Odometer / Speedometer goes:  Try this:

http://www.1010tires.com/TireSizeCalculator.asp