Classic Style

I'm trying to upgrade my mechanical speedo to an electronic one, and I put a 76 915 trans with the electronic speed sensor into my 74 911. I have a 12v source hooked up to 1 wire on the sensor, a "signal" wire hooked up to the other wire, and the signal wire goes to the "31b" terminal on the Speedo. Another 12v source goes to the "+" terminal on the speedo, and the "-" terminal just goes straight to ground.

The problem is, the speedometer at ~5+ mph reads 40, and its just basically way off all over. Any help would really be appreciated!

Thanks
Rand

DGaunt

I suggest you call Palo Alto or Hollywood Speedo. I wonder if the speedo is not calibrated to the sender you have? At least you get SOME reading.

There will be others who know more, I'm sure.