How to run a tach with a mag

Need some help any ideas.

 

Google gives you SEVERAL solutions including vendors.

 

mechanical

 

Or you can maybe fit one of the electronic crank position sensors used with EFI engines to drive your tach.

 

Autometer used to sell one that would work without a sender. Full electronic.

 

No sender ???
How can it tell how fast the engine is going ??

 

The old Autometer plugged into the mag. It didn't require 12 volts. I ran those in the dragster in the 80's. Finding an old one would be the only hope. I changed over to cable drive in 89 because I had no battery on the car.

 

auto meter makes a unit for adapting a modern tach to a mag ignition, run it off of a small motorcycle battery (easy to hide on a FED)
http://www.speedwaymotors.com/AutoMeter-Tach-Adapter,103.html

Paul