[Vrroom]

I'm installing 3 levels of theft deterrent on my 1969 GTO. One is electrical and the other 2 are mechanical. The electrical choice is going to be an ignition kill switch, which leads me to my question.

On an engine with an aftermarket HEI distributor, I've been told there are two ways to install an "on/off" kill switch. One is to splice it directly "in line" within the wire going from the fuse box to the distributor. Flipping the switch essentially disrupts the power to the distributor.

The other way is to run an additional wire from the distributor connection point to a ground and have the kill switch installed in that wire. Flipping the switch essentially "grounds" the distributor, thereby keeping it from being able to send fire.

Which way is better?

[Pontiac Slim]

Hey..
I ran an off/on switch between power source and dist.. Suggested by automotive electrical guy. Been on car for 10 yrs with no problems at all.
Pontiac Slim

[runningbwdog]

Hi,
If you go with Option 2: Ground through a switch to the dist, you could drain the battery or worse yet, if your wire isn't big enough you could melt the insulation of the wire and start a fire. I suggest you go with a fail safe system.
Mike

[george kujanski]

In option 2you say running a wire from the "distributor connection point". What exactly is that point?

In general a grounding switch is not as good an idea a bwdog says because you will be drawing current thru something, like the coil, and cause damage.

George

[Vrroom]

Here's a picture for clarification. The pink wire is always hot when the ignition switch is in the "run" position.

Seems like the consensus is to go with Option #1.

[RAIV55]

Definately option 1

Option two will do one of several things with the key on,
Blow the fuseable link
Start a fire
Toast the switch
Drain the battery

[Vrroom]

I doubt the wire from the fuse block carries that much current seeing that it's energized anytime the car is running, however I'll stick with the traditional #1.

Thanks,
Vrroom

[RAIV55]

Originally Posted by Vrroom

I doubt the wire from the fuse block carries that much current seeing that it's energized anytime the car is running, however I'll stick with the traditional #1.

Thanks,
Vrroom

Being energized and grounded are two different things.

[george kujanski]

Per the dwg: you definitely do NOT want to do option 2.

George

[Geoff]

My kill switch grounds one of the dist magnetic pick up wires. Only requires one small gauge wire wire to the dist.

[79firebird_99TA]

Option one creates an open circuit and option 2 a short. The first time that you go to crank the car with option two and the switch closed, you'll have to replace the fuse.

Go with the option one - open circuit.

[mikeb]

Option #2 would work on an older style ignition with an external coil with both the +/- terminals if you grounded the - terminal with a switch. Might burn up the coil if power was left on long enough though.

With the HEI you should go with option 1.