Speedometer

In the previous post I discussed the idea of creating a virtual trigger wheel and using the stock MB speedometer sensor. In this post I want to take a look at another potential alternative.

This idea comes courtesy of Patrick Schalles in an article titled How To: Installing a Universal Magnetic Pickup Speedometer Instead of using a MB speedometer he is using a universal speedo e.g. the AutoMeter one.

Instead of using a variable reluctance system he is using a Hall-effect system using magnets instead of "teeth" on the driveshaft. This sensor kit is about $25 from Rostra Precision Controls.

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This system uses a different signal but from his article it appears that we might be able to use this signal by putting it through a GM VSS Buffer to convert the AC signal to a square wave signal. I'm not an electrical engineer but it seems plausible that the signal from the VSS Buffer might be able to be fed into the wiring of the MB sensor and get a signal that way. If this is possible, it means that instead of relatively close sensor-to-trigger-wheel gaps we could theoretically go with the easier and more forgiving tunnel mounting and 1/2" recommended gap.

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I actually spent about an hour looking for one of these devices at the JY this weekend to no avail.

A follow on solution using this strategy might be to somehow insert the internals of an AutoMeter speedometer into the MB cluster. Probably not something I'd try, but maybe a path for someone to pinneer.

Anyone have any opinions about whether this kind of a signal might be suitable for a direct feed into the MB system?