Jaycar electronics £14.75

Digital Speedo Corrector

CAT. NO. KC5380

Ref: High Performance Electronic Projects for Cars - Silicon Chip Publications.
If you upgrade your gearbox, change diff ratios or even change to a larger circumference tyre, you could be plagued with an inaccurate speedo. It alters the speedo signal up or down from 0% to 99% of the original signal. The adjustment is easy to dial in using multi position switches. This unit could avoid traffic fines, which may result from using a non-calibrated speedo. It is also suitable for altering speed sensor input reading to the ECU or auto transmission control computer. Kit supplied with PCB, and all electronic components.
* Requires car to be fitted with electronic type speed sensor. It will not work with a cable type system.



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Rescued attachment speed.jpg

If you've got an electronic speedo shouldn't there already be a facility to calibrate to wheel size, etc.?

I guess if anyone's using a donor electronic speedo without a built-in adjuster it could be useful??