Do It Yourself Install Tachometer for 4, 6, or 8 Cylinder Engines
Here is a picture that shows the engine cylinder adjustments if you want to diy install an Autogage 3 3/4″ tachometer for operation on 4 or 6 cylinder engines. By default this tachometer is factory calibrated for 8 cylinder engines, then a switch adjusment must be made.
How to DIY Fix Tachometer Solder Joints of Mazda RX-7′s
If you find that your RX7′s tachometer performed a bouncing needle, the following article may give you insight in diy repairing your Mazda RX7′s tacho.
Do It Yourself Making Wireless Automotive Tachometer
In order to contruct yourself a wireless auto-tachometer, you will need the information about the PCB layout and parts placement in addition of what parts needed to accomplish the project. And here, you will find all the information required to design your wireless automotive tachometer including how to calibrate the tacho.