Recalibrate the Speedometer

How do I recalibrate my speedometer? I bought some new faceplates for them because my car goes faster than the OEM 120 and when I get above that I don't know how fast I'm actually going. Therfore I needed new gauge faceplates. I got 'em but now I don't know when the speed is right at all because I don't know how to recalibrate them to accomidate the 140... Anybody?

i don't think you can. you gotta get a new gauge cluster, preferably one from a jdm car, with the higher speedo. since it is a electronic cluster.

oh, shit I thought you could? I've heard of it being done before... or so I thought.

I think that you used to be able to recalibrate old speedometers, like ones off of cars built before the 70's.

Nowadays it's all loaded on with computer programs. I think that you gotta get a new guage cluster, unless you have a program to plug a computer in and do it with. I only think that the automakers can do it.