2 replies to this topic

[RacingGreen]

I wanted to change the dials in my car (998cc Racing Green) to a set of the green 110mph dials.

As the speedo currently in my car is a 90mph clock how would i go about getting the 110mph speedo to read correctly?

Is there any other way apart from having the speedo re-calibrated?

Thanks

[Guess-Works.com]

It depends on a lot of factors, namely the diff, and the speedo take off ratio, and finally the turns/per mile of the speedo...

As most minis with the exception of the real late ones wer still using 3.44 diffs, you'd probably get away with it...

[dklawson]

Well... how often do you drive 110 mph? If you're like me and drive like an old lady, you seldom get above 60 mph. Your 110 scale on a 90 mph face will read about 20% low (assuming both gauges have the same full scale degrees of sweep). So, indicated 50 will really be "60". As GuessWorks said, perhaps you can just live with it. If not, there are tricks you can try at home but they involve removing the gauge and accessing its works.

If you select some small (and I do mean small) rare earth magnets, you can selectively add them to the spinning disc inside the speedometer. This will increase the eddy currents and therefore give you a higher reading for the same input RPM. How do you know you've got it right? Sharpen a nail into a square that fits the drive hole in the speedo. Chuck the nail in your (low speed) electric drill, set the drill in reverse and drive the speedo at about 1500 RPM. Note what this reads on your 90 mph gauge face and compare where this should be on the 110 face. Add a couple of magnets and repeat the test. When your needle position gets close enough to where it needs to be... you're done. Generally the magnets stay put. However, if you drive like a mad man, you can put a drop of Krazy Glue (cyanoacrylate) on the magnets to hold them in place. The magnets can easily be found on eBay.