Can't help you with the "Tire Rack" question, but if by "20% short" you
mean an actual kilometer traveled shows as 8/10ths of a kilometer on
your odometer, then you must multiply the kilometers shown on your
odometer by 1.25 and you have actually traveled 250,000 kilometers.  If,
on the other hand, your odometer read 1.2 kilometers after traveling an
actual kilometer you have 166,670 kilometers actually traveled in your
Westy...unless I'm wrong.

-Dana-

Dick Bowie wrote:
>
> Hi there
> I looked on the Tire Rack website and could not find the section which will
> show me the rev/mile. My speedo shows 500 rev/km.
> I recently drove thru a measured km and discovered my odometer is off 20%
> (short). I assume the speedo is off by the same variable.
> This means my '88 Westy only has 160,000 km's and not 200,000 km as shown by
> the odometer. This is good news.
> Bye for now, Dick
> '88 Westy
> '90 Miata