Here is my last post regarding them. [ http://www.twinturbo.net/nissan/300zx/forums/general/view/2489233/GoodBad-news-regarding-the-new-style-200-mph-gauges.html ]I went ahead and bought the Dakota Digital Universal Signal Interface and received it today. Fast shipping from the eBay seller where I bought it. The results of the testing turned out great so the new style 200 mph speedometer gauges are now going to be available. This is how I was able to get it to work.... The new style speedometer board has a chip where the speed sensor signal is first input to. The chip splits the signal into four outputs. One of the outputs is sent to a chip which converts the signal to either MPH or KPH and drives the meter. I took the signal to that chip buy cutting the trace and routing it to the Dakota Digital signal interface and then sent it's output to the chip. With the interface in line to the meter driver IC you can now modify the signal using the up/down buttons on the signal interface to calibrate the gauge display. The signal that the ECU sees stays the same because it gets its signal from one of the other outputs of that first chip where the speed signal is first sent to (the one which splits the signal into four outputs). Here are some pictures showing the calibration.
 






Just like the 1990 gauges, once you hit 160 on the meter you are actually doing 155 (or 5 mph less) as reported by the ECU.
 


The cheapest I've found the cost of the Dakota Digital interface was on eBay for $80 shipped. What I will do for anyone who would like this modification is to adjust the cost of everything to the same price I had for the older style gauges. I will also put some info on my website on how to do the modification. This way you should be able to save some cost on doing it yourself. A picture of the Dakota Digital Universal Signal Interface.

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