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Help me: Wiring cut off switch

Old 09-18-02, 05:34 PM
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Help me: Wiring cut off switch

My head is spinning, I'm not good at electronics or wiring, so please help me figure out what I need to do here. Reference this graphic that I found.
http://www.ssdiv.com/killsw.gif
Ok, so the battery wire goes to one of the two big poles. A wire then goes from the other big pole down to the starter. That far I understand.

Now, based on this pic, and other descriptions, It looks to me that I'm supposed to also wire the alternator output wire to one of the two big poles. But which one? The one running from the battery? or the one running to the starter?

Ok, I'm also supposed to run a wire from the starter side of the big pole to one side of terminal 1 (normally closed). The other side of terminal 1 goes to the supplied resistor, and then to a ground. Correct?

Now, terminal 2, is supposed to go inbetween the ignition switch and the coil. However, we have multiple coils in the 2nd gen RX-7. so which wire do I splice this into? Sorry, not good at reading wiring diagrams.

Thanks for any help you guys can offer. THis is for a 2nd generation RX-7.

PaulC
Old 09-18-02, 06:03 PM
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the way I have done it is to use the normally open contact(switch open when handle is in off position) and break the power to the coils. this stops the engine from running. you may need to cut both of the 12VDC+ wires if there are two seperate feeds to the two coils packs(not sure of OEM wiring as I have rewired my entire race car). since the source is the same you can connect them on the same switch contact, or you could use a two pole relay to keep the feeds seperate. main battery cable is easy. As for the alternator to ground through the resistor I have found the resistor to be to small and not effective. I do not connect this just don't use the emergency shutoff switch to shut down the engine all the time(emergency only), repeated shutdowns at the switch without the bleed may cause damage to the alternator diodes(not ever happened to me on 5 or 6 race cars I have owned or worked on). just use the regular switch you have for the ignition or the key if it is still installed(the steering lock should be removed though).
Old 07-26-09, 09:13 PM
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No traffic on his thread since 2002, and no other related threads...!? I can only conclude that the topic is basic and easily understood by everyone.... except me. I didn't follow the answer.

I need a safety kill switch for racing; everyone does, right? Summit or Longacre or whomever sells two basic types, 2 pole and 4 pole. They say 4 pole is for cars with alternators. I have an alternator (doesn't everyone one??). I haven't bought 1 yet, so I don't know what the directions may tell me. I'd like to get some direction in advance of that. Asking for a helpful explanation.

Thanks.

Last edited by almost heaven; 07-26-09 at 09:14 PM. Reason: My "t" key sticks
Old 07-27-09, 12:36 PM
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Found some info under "battery disconnect".
Old 07-28-09, 01:04 PM
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Originally Posted by almost heaven
I need a safety kill switch for racing; everyone does, right? Summit or Longacre or whomever sells two basic types, 2 pole and 4 pole. They say 4 pole is for cars with alternators. I have an alternator (doesn't everyone one??).
Some cars (eg. SCCA Production Class) can run a lossy system - battery only, no alternator.

This question is asked so much that it's stickied in the Improved Touring forums:

http://www.improvedtouring.com/forum...ad.php?t=20130

-b
Old 07-29-09, 05:19 PM
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Thanks for the reference! Pegasus 4430 switch ftw!
Old 08-08-09, 10:56 AM
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Originally Posted by almost heaven
Thanks for the reference! Pegasus 4430 switch ftw!
Could you please explain how you wired yours?
Old 08-15-09, 02:27 PM
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Haven't wired it yet, but this is my plan... Battery is already relocated behind the pass seat. Hot wire runs thru the firewall and splits to alternator and starter. I plan to just cut the hot wire back by the battery box and install the switch there, then cut and run the ignition wire back to the kill switch and return back to the place I cut it. This looks like a pretty good explanation to me.
http://www.pegasusautoracing.com/pdf...structions.pdf

Then, I'd like to run two thin cables from the kill switch key, one to driver's side window and one to pass side window, and mount the cables to the cage there once it is installed. Idea is to have a pull cable to the kill switch accessible from each side of the car by reaching thru the open window. Will exceed safety requirements, since it will work from both sides not just one.

Don't forget to cover the bottom terminals of the kill switch to prevent shorting sparking in the event of an accident. Pegasus also sells some covers for that.
Old 08-16-09, 07:19 PM
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Originally Posted by almost heaven
Haven't wired it yet, but this is my plan... Battery is already relocated behind the pass seat. Hot wire runs thru the firewall and splits to alternator and starter. I plan to just cut the hot wire back by the battery box and install the switch there, then cut and run the ignition wire back to the kill switch and return back to the place I cut it. This looks like a pretty good explanation to me.
http://www.pegasusautoracing.com/pdf...structions.pdf

Then, I'd like to run two thin cables from the kill switch key, one to driver's side window and one to pass side window, and mount the cables to the cage there once it is installed. Idea is to have a pull cable to the kill switch accessible from each side of the car by reaching thru the open window. Will exceed safety requirements, since it will work from both sides not just one.

Don't forget to cover the bottom terminals of the kill switch to prevent shorting sparking in the event of an accident. Pegasus also sells some covers for that.
Thanks man for the PDF file and I will go with the Pegasus switch too.
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