Mechanical to electronic speedometer solution

[fast NY Six]

After researching this subject for many hours, and not finding a satisfactory solution. I wanted to keep the car as stock appearing as possible. I am also cheap and didn't want to regauge the whole dash. I figured if I can mount the speedometer stepper motor in place of the mechanical setup, it could work. New vehicles gauge clusters are all one circuit board but in older vehicles there is separate Board for just the speedometer. I found a gauge cluster out of a late 80s lesabre. I removed the stepper motor and board. Then mounted to the regal faceplate. A simple three wire hookup. Keyed ignition, ground and pcm output. I still have to figure out mounting it into the housing but it's definitely possible. I hoping to get the odometer in there too somehow.

 

[1986TR]

Very interesting keep us posted on the progress ... I have a 80 cutlass with a 4.8/4l80e and the speedometer is the only thing I haven't got working on the stock dash .....

 

[fast NY Six]

It's not pretty but is should work fine. I had to do some carving to get it to sit in the housing. I probably could have removed the board from the stepper motor and did less carving. The motor for odometer hung way off the back so I relocated it to the top of the bracket. I glued some posts in the housing to keep my depth correct. I was debating soldering wires directly to the board but ended up soldering the
Wires to the flimsy foil like leads the were part of the circuit board so I could maintain the connector. I'll post more when I'm done.

 

[fast NY Six]

Finally got it together. The odometer is right on the money. The speedometer is slightly off but might be ok once installed in the '86. It might need to be tweaked with hp tuners. I had to solder the three wires directly to the board.