[marshmanjr]

Hey everybody I have an 82 Dodge Ram Charger and i have 31s on it right now. I have been wondering what the orginal tire size the tires were that the factory calibrated the speedometer to so i can find out what speed i really am doing, plus to figure out gas mileage.

Any help would be great.
-Thanks

 

[JasonB]

Can't help you with tire size, but use a GPS or time between the mile markers on the highway (use several miles worth to get the average speed) and that will let you determine the corrected speed.

 

[tv_larsen]

I believe that they had 225 or 235/75R15's from the factory.

 

[wickedakota]

They were 235/75R15's.