Sup, i broke the needle off my 145 mph speedo, so i left the face plate off and now im driving around watching the magnet spin... i was wondering if i took an 85 mph speedo or 120 mph or whatever the lower one is and changed the faceplate, if it would be accurate... whats the difference between the two?

im assuming the speedo cable spins at the same rate and the 85 mph or whatever speedo pretty much fills the entire range across the face plate, so is the cup part farther away from the magnet or is there a difference in the cables themselves?

there are lots of 85 mph speedos around, butnot as many 145 mph...

 

All speedometer cables spin at the same rate for distance covered - therefore, at the same speed, two different cars will have their cables spinning at the same speed (in a perfect world, anyway).

It's what the different speedos do with the input that is different. Magnet strength, spring strength, distance, damping, etc., are worked together to make the speedometer read properly for a given vehicle (or cable rotational) speed.

Why not just replace the needle?

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