Gerneral Question About My Speedometer Being Off? Anyone?

[NeedForSpeed]

My speedodmeter is off in my F-150.

I switched from 255\70\16 wheels & tires to 285\50\20

The new wheels and tires are bigger, maybe 2or 3 inches etc... taller.

How would this effect my speedometer?

Would it make it read faster or slower?

For example if I was doing 30 on my speedo, I'd really be doing..... 35 or 25? etc..

 

[Ryan]

IIRC, there is a way calibrate the speedo with the digital instrument cluster for testing etc..

 

[boostdacr]

i think u just hold down that knob and turn the key on..and you should get a menu of things...might be able to do it there

 

[stubbs]

it will make you milage off and the speed would be different.