[ACONLP]

the car is a 1967 v8 car. the coil wire, can i use it for a 12v ignition power. need a 12v source to run the computer for my Ls1 swap. what is throwing me off is, the fact of how small the wire is and on a wiring chart, it says that it is a resistance wire. what do they mean by that. can i use this? or is there some where better to get a 12v ignition. the car is still using the factor wiring loom.

 

[TomM]

The coil wire is switched from the key, and yes it is of different construction to provide around 9v to the old style coil, in lieu of a hard wound resistor used on later models. You need a constant hot to the computer....not switched....

Get your test light and test the factory fuse box. You will find terminals under there that are switched, and unswitched....if you switch the computer off, it will have to "relearn" itself every time you turn on the key.....

You can use the switched hot for the fuel pump relay etc.....computer for the full time hot. There should be a fuse box in your new harness to connect to battery hot to feed the computer and other items in the harness.....

T,

 

[ACONLP]

yeah i have a 12v power and 12v ign. the ign is what i was wanting to hook up to that old coil wire.

 

[NovatoriusRex]

You can easily pull the engine wiring harness off of the firewall plug and replace that resistor wire with a non-resistor wire and then use it to feed accessories that need a full 12v when the car is running. Prior to that wire exiting the firewall plug, it has a full 12v from the fuse box. It's only downstream, at the end of the resistor wire that it's stepped down to 9v; it's stepped down in voltage along the length.

I accomplished this with my car by buying a replacement engine harness to replace my original one. In retrospect, paying someone to do it was a waste of money. It would have been incredibly easy to do myself, but that was before learning a bunch of stuff from the guys here.

If you're handy with a soldering iron, and can easily manipulate the firewall plug fitting onto a new wire, it should be a cake walk of a task.

 

[snolan]

Harness

Speartech did my LS harness they had a fuel pump lead .. i had American auto wire build me a whole harness striped of all the votage reg stuff ..and feeds for the in the tank pump connections plus all of the needed one wire alt connections.


worth every penny$$$$

nice and clean

Steve