Switching tires from 14 to 15

[Mikey59]

Switching tires on my charger from 60 /14 to 60/15's . How many teeth on the speedo do I need to run in my transmission I've got a 727 auto. ?

 

[496 polara]

Need the tire diameter to use one of the charts available.

Mopar Speedometer Pinion Numbers

 

[sam dupont]

You can find 15 inch tires with the same diameter as the 14

 

[dan juhasz]

brewers has a nice chart on their website, you can look up approx tire diameters on sites like tire rack.

 

[multimopes]

 

[multimopes]

If you are buying new tires, don't believe what the manufactures tell you. Measure them yourself. I bought some tires advertised as 28" tall, but I measured 26" unmounted & 26.5" mounted and inflated! You couldn't get them to 28" unless you put them on a dragster with thousands of horsepower spinning at full throttle!

 

[Dave6T4]

Looking at Brewer's chart, it looks like Chrysler meant their cars to run with a 26.5" tire. That way, you could just take the first two numbers of your rear gear, and that is how many teeth is needed on your speedo gear.