'94 GT battery relocation

[Fasterthangas]

Decipha;

What's your thoughts on this comment? I'm going to relocate my battery to the trunk and I'm concerned about the mentioned voltage spike.

"If you go racing, some tracks or sanctioning bodies may require a Master cut-off switch because you moved the battery. That makes the diagram a little more complicated. See this diagram for the setup. You have to use a "four terminal" master cut-off switch (Taylor #1033 or Moroso 74102) and an alternator cut-off switch (Painless #50105) to cut-off the juice from the alternator AT THE SAME TIME as you cut the battery. If you do not do this, the voltage will spike (18+V) and damage the ECU or ignition. This happens because the battery acts like a stabilizer in the electrical system. Without it, the alternator will try to compensate and Boom. Bye bye ignition and ECU. Very expensive mistake. The Painless #50105 must be switched via a relay so that you do not drain the battery when the car is not running. Find a circuit that is HOT in START and RUN and tap from it to energize the relay. By the way, the Moroso switch is a little on the overkill side with a 300A continuous rating. The terminals are also designed for 1/2" lugs. That is larger than standard (3/8")."

[decipha]

that doesnt apply to EECs they can handle 19 volts no problem.

[Fasterthangas]

Perfect. Thank you!

[wwhite]

that doesnt apply to EECs they can handle 19 volts no problem.

19 volts constant, but what about voltage spike or surge? as well as current spike or surge?
- specifically when the vehicle is running, and someone hits the 'kill' switch, when it is wired incorrectly.

Not only the EEC could be at risk, but what about the rest of your electronics in the car?

Make sure you use the correct size wire.

Here are a couple of really good articles:
https://adaptronicecu.com/blogs/article ... age-spikes
https://moretraction.com/wp-content/upl ... To_Web.pdf

[decipha]

I used to run 24v at WOT on my cousins 95 GT that I daily drove for years. It would go from 14v at idle and cruise then snap to 24v at WOT due to a bad alternator regulator. Never a problem.