Kill Switch Wiring
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Short answer, no added fuse needed on the power side of the coil.
The kill switch if it was wired to ground and the negative side of the coil would be like the points being closed. Normally on a running engine the points are opening and closing and the amperage draw is less than if one turned on the ignition without the motor running and the points were closed. On a running engine the coil might pull a couple of amps and then if the motor was shut off but the ignition left on, the draw might be a tad more providing the points were closed BUT if the points were open, then no draw as the circuit is not completed through the coil.
Per some information from the GM Heritage site on a Nova (sorry but this is what I have bookmarked for my own use) is that the ignition coil shows amperes drawn with engine stopped 4.0 but when running at idle, 1.8
While you can wire kill switches on the power side or negative side of a circuit, I prefer opening up the power side. There is no real right or wrong side and I've done it on either and/or both sides depending what I feel is the best.
However you do it, make it safe and run the wires properly so a short cannot occur between the coil and the added switch of yours.
Jim
The kill switch if it was wired to ground and the negative side of the coil would be like the points being closed. Normally on a running engine the points are opening and closing and the amperage draw is less than if one turned on the ignition without the motor running and the points were closed. On a running engine the coil might pull a couple of amps and then if the motor was shut off but the ignition left on, the draw might be a tad more providing the points were closed BUT if the points were open, then no draw as the circuit is not completed through the coil.
Per some information from the GM Heritage site on a Nova (sorry but this is what I have bookmarked for my own use) is that the ignition coil shows amperes drawn with engine stopped 4.0 but when running at idle, 1.8
While you can wire kill switches on the power side or negative side of a circuit, I prefer opening up the power side. There is no real right or wrong side and I've done it on either and/or both sides depending what I feel is the best.
However you do it, make it safe and run the wires properly so a short cannot occur between the coil and the added switch of yours.
Jim
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Yep, there are things such as HEI ignition systems and for some reason I assumed you had the old style points
.In that case, to me there are more electronics with an HEI compared to the old style points system and if it was myself I would shy away from grounding the coil out but instead open or close the power getting to the HEI (sometimes labeled as BAT but is actually an ignition 12V feed and who knows how MSD labels this).
Years ago maybe around the 1990's, Alpine electronics started into the alarm/security business for vehicles and they had a very neat starter kill switch that would actually mount under the hood somewhere and if for some reason the alarm kept the relay open you could open the hood,know where this special relay was at, flip a rocker switch underneath a rubber waterproof lid and bypass the switch. While it was designed for starter interupt, one could wire it into an HEI ignition system.
Jim
I hate kill switches, it only introduces another failure point in an ignition system. Is there that much of a chance that your car is going to be potentially stolen? In addition most thieves do not start the car and drive away, its hauled off on a tow truck.
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Good point. I had a kill switch on same car for several years. It was to the power + to a different HEI. One evening as I pulled up to my house I left car idling in front of house while I moved another vehicle. All of a sudden it lost all electrical power. I had to jump it from the battery to the coil just to run it while I got it into the garage. Next day while I was trouble shooting it just started working again. However my kill switch no longer worked. I tested the toggle switch and it was good so something else must have shorted.
To be honest the time that worries me most is when I’m at a big car cruise and leave my car to see the others at the show and my car is unattended. If someone wants to steal a car that is the place as nobody would know who the owner of a particular car was. A well timed stealing would most likely get little attention and a thief has lots of choices.
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Kill switches can be useless in some situations and can fail. Depends on the situations, installations, and parts chosen.
I still get a kick out of an install I did years ago with a fake alarm flashing LED. This customer had a beat up old truck and I put in a nice radio and a couple of years later he came back to upgrade the radio and I asked him how the heck is that radio still in the truck from being in the bad neighborhood you live in and his reply was: Theys afraid of the flashin light and leaves it alone.
Jim
I still get a kick out of an install I did years ago with a fake alarm flashing LED. This customer had a beat up old truck and I put in a nice radio and a couple of years later he came back to upgrade the radio and I asked him how the heck is that radio still in the truck from being in the bad neighborhood you live in and his reply was: Theys afraid of the flashin light and leaves it alone.
Jim
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Personally I would never let it out of my sight regardless of where I am. I could never go in a restaurant with out sitting near a window to see it. Yes, it limits what you can do and where you can go but I still have it. I drive a beater to car shows as I like looking at others rides and basically no one gets to lay eyeballs on my baby. I can lock the hood down if needed but no kill switch. Am I paranoid? You bet but better safe than sorry. Good insurance is a must too. Agreed value seems to fit the bill.
I won't get into the debate on weather kill switches are usefull, might as well debate what oil you're using.
I used a relay to interrupt the starter circuit. The relay is operated in any number of ways. I used a hidden toggle switch, but this could be any number of sources.
The function of the relay not being switched before attempting to start the car causes the horn to sound at a constant beep as long as the key is turned to "start" without the toggle being switched.
As an additional benefit I'm running an "e stop" electric parking brake. The function of the parking brake is also disabled through the same relay used for the starter.
So once I park somewhere and disabled the relay, if anyone attempts to start the car they get a solid horn blast. And they will not be able to roll the car very easily.
Sent from my SM-T720 using Tapatalk
I used a relay to interrupt the starter circuit. The relay is operated in any number of ways. I used a hidden toggle switch, but this could be any number of sources.
The function of the relay not being switched before attempting to start the car causes the horn to sound at a constant beep as long as the key is turned to "start" without the toggle being switched.
As an additional benefit I'm running an "e stop" electric parking brake. The function of the parking brake is also disabled through the same relay used for the starter.
So once I park somewhere and disabled the relay, if anyone attempts to start the car they get a solid horn blast. And they will not be able to roll the car very easily.
Sent from my SM-T720 using Tapatalk
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Senna,
Your set up sounds interesting. I already have the mad electrical system which uses a relay in the start system. Wonder if it could be retrofitted to operate the horn such as yours does?
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