There are links to three basic types of information in this tech section.

What does SAE mean and why is a wire specification important?
What are the specs covering automotive wire and why should you care about them?
Answers

• For help with the hands-on fabrication of a reliable system
• For a fast answer for what size and type of wire to use in a specific location with a reasonable safety margin
• For tips for making a safe and reliable wiring job with a minimum of cost and effort
• For some options to make it easier to work on when the inevitable changes come along, (especially for racers).
More

Choices you can make regarding wire size and insulation
and why, what to look for when buying wire, info about wire insulation, stranding,
weight of wire, rated current capacities and more. There is enough information here for a person with an understanding of Ohm's law to do a detailed design of an automotive wiring system. Click here for  wire tables   and
current vs wire size, ( both SAE and DIN ) specs