Battery cut off switch

hotrodhoodlum said

Can someone post a diagram of a 2 post battery cutoff switch with a 3 wire alternator and a start button . This the first time for me wiring my race car from scrach . I have a painless 8 circuit race kit and have not started yet . Can someone lead me in the right direction for good instructions on wiring Mopar Charging and Starting system is what I need help with

Thanks

Click to expand...

The problem I have with a "2 post" (properly called a SPST) switch:

Many guys run a separate wire from the battery to the alternator output, especially with a "one wire" in order to get the kill switch to kill the engine.

The problem I have with that is that this leaves (at least about a no 8) a hot wire all the way from the battery to "up front."

NHRA rules has some statement that refers to "kills all power," and doing things that way will NOT "kill everything."

The OTHER problem with a 2-post switch and a 3 wire alternator is figuring out a way to kill the engine.

You must understand that when you take a running engine with an active charging system, unhooking a battery cable will NOT kill the engine. The alternator keeps things running.

Using a "4 post" (properly called a DPST) switch cures all this, because you use the smaller terminals to activate a relay which drops out ignition and or alternator field/ regulator circuits.