What have you guys done for gauges if your MIata's won't work like mine? I have order some autometer temp, oil, fuel gauges but the speedometer and tach I haven't ordsered yet. Who has wired a T56 to an Autometer tach and how did it work out? Did you need a converter box? If so who sells it?

My 2001 NB stuff doesn't work with my wiring harness and bulkhead wiring connection. I understand that my 2010 harness is a 2 pulse tach output and it doesn't move in the Miata or does the oil pressure (only the fuel level works) so it is going to have to be autometer stuff.

 

I get oil pressure from a dual output VDO gauge sender to run the dummy pressure gauge and also run a VDO gauge. My tach works fine as I have said but recently when I buttoned stuff up again after having the dash out I realized that my speedo was erratic so I ordered a Dakota Digital box which should be here this week. They sell a tach adapter too. The speedo adapter is about $80.

 

I used an autometer speedo and tach. To calibrate the speedo you have to mark 2 miles on the road. Push the button drive the two miles and push the button again. Very simple.

 

MX5.7 How did the process go cutting the dashpanel and installing the new tach and speedo? Is yours an NA or NB? Did you have a circuit wiring mate on the back as my MB does? I like how yours looks. nice job!

 

I have the Autometer six pack in my Miata. As was told, one drives the car for two miles to calibrate the speedometer. I drove one of my other cars for two miles and indicated the start and end points. Then, I drove the course. I had to do this for the LT1 RX-7 I owned. The Miata was already sorted out, when I bought it. I'm not sure where the pulses are picked up for the speedometer; but, the speedometer counts the pulses in the two miles and calibrates itself, accordingly. Actually, one should do this when one changes tires that might be slightly different in diameter, wheel diameters, etc.

As for the panel, Tim Devlin built the car and made a nice panel insert using flat aluminum. On it are the tach, speedo, water temp, fuel gauge, idiot lights, etc. The volt meter and oil pressure gauges are located on a flat aluminum plate below the radio. There is even a low oil pressure idiot light on that panel for those times when I might fling the oil too hard to one side of the oil pan. I've actually seen that happen, a couple of times. Neat!

 

I had to go with the tach adapter from Autometer and (gulp) cut the harness coil wire and it works great. The speedo says to connect to the high side of the T56 output wires. Anybody know which one that is???
After that I found the autometer fuel gauge doesn't work with the Miata sender. It is a 115ohm empty and 3ohm full setup, so that is backwards of the Autometers 0-90 ohms. It works sort of as it is backwards and runs out at about a half tank. anybody found a sender replacement for this setup???

 

Autometer used to sell a sending unit that I adapted to where the original miata sending unit is located. It looks identical to this http://www.summitracing.com/parts/VDO-226008/ . I unbolted the top half and threw it away, using only the actual sending unit to bolt to the miata bracket.

 

Thanks for that info, it looks like it can be adapted and the ohms are right. I'll ask autometer first before I purchase that one.

 

Any updates on this? I need to start looking into gauges for my build