I originally posted this in the Q & A section and it fell off the page. A few guys that normally hang out here answered so I apologize for the redundancy.

I have my car wired like in the diagram. I am looking for confirmation as to whether this will be OK.

Please let me know if there is anything that I should do differently or that appears to be wired incorrectly.

The terminal block by the firewall is from the Mad Electrical Start up kit. The alternator is a Denso 60 Amp. The cut off switch is a Taylor STDP #1033. The small studs are rated for 20 amps. The starter is a Denso mini starter. The battery is a red top in a Moroso box. The MSD is a basic 6AL.

I have been messing with this for a while now and keep re-thinking (over thinking) what I am doing. I need to put this to bed so I can move on to the next project. Thanks for any input.

Read the following article on using shunt diodes, hope this helps, Tim
http://www.cessna120-140.org/forum/files/solenoid_diode___pulses.pdf
You also need to mount the solenoid sideways, the acceleration could cause the weight of the shaft can overcome the spring and cause the starter to engage. Tim

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I have been messing with this for a while now and keep re-thinking (over thinking) what I am doing. I need to put this to bed so I can move on to the next project. Thanks for any input

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It looks over complicated to me but I don't know what you are trying to accomplish? It could be done better with a latching solenoid imo.

Latching solenoid?

What are you trying to accomplish?

I am trying to:

1) wire the cut off switch per NHRA rules - kill power on B+ side and also kill the alternator output when cut off switch is turned off

2) wire the Ford starter solenoid to allow battery cable to be run inside the car - "only hot when cranking"

3)Per Mad Electrical, ammeter bypassed, circuit spliced, would like to run the dash "main feed" wires to rear cut off switch to kill power to ignition switch when switch is off

"Alex, I'll take 'making thing way more difficult than they need to be' for $2000"

I would not run it that way.

A latching solenoid is a high current relay that latches in either the on or off state - Push the energizer button once and it opens and stays there (latches) push the button again and the solenoid closes and stays there. The solenoid will not "bounce" or "cycle" if the switch is held down constant.

I use them to kill power from the battery to everything in the car. One advantage is it takes no current to keep latched. If you run your alternator charge wire to the battery or before the latching solenoid it would work for what you want to do. They are very reliable.

http://www.colehersee.com/home/item/cat/182/24200/

Buy them here

Google - Cole Hersee 24200

A)Is this a street/strip car or a race car?

B)How much of the stock harness are you trying to keep?

C)Have you read the NHRA rulebook General regs part 8 electrical?

D)Is jeopardy your favorite game show?

What I see right off is:

A)You did not show any connection to the existing fuse panel. The 20amp switch contacts and #14 wire will not directly feed all the existing loads in the car (lights, wipers, heater fan, etc). Also remember some of the fuse panel is hot all the time and some is fed from the ign. switch.

B)you show no circuit protection (fuses, cir. breakers, fusable links) on anything new. Mainly the "Main dash power"

C) when designing electrical circuits and systems you NEVER want to max out the ratings of anything.

D)The starter solenoid would connect to the start (crank) connection of the key switch

Sorry, I should have made it more clear but I didn't realize you were asking if I took all the wiring out of the car. Most of the wiring is in fact still original. The one section that was taken apart was the forward engine harness which contains the ignition, starting and charging circuits. That whole harness is apart/out and whatever associated wiring for those components that normally pass through the bulkhead is out. The ammeter has been bypassed.

Though I don't have much in the way of accessories running, the main under dash harness, ignition switch and steering column harnesses are still being used and anything from there that goes to the fuse panel is still in place. Plus the head and tail lights, turn signals and dome lamp.

As far as protecting circuits, the alternator output wire to the cut off switch is protected by a fusible link. The main dash wires going back to the cut off will be protected by a fusible link.

I did not plan on using any protection on the battery cable since the starter solenoid takes care of that.

I figured that running the main dash feed back to the small stud on the cut off would be OK since there is little in the way of accessories - no radio, climate controls or what not so in my mind there won't be much current running through it at any given time. I can always use relays to further reduce current, like with the headlights.

The main question here is whether or not the set up will work the way the diagram is configured while being able to satisfy safety requirements when I take it down the track.

If I'm seeing it correctly your alternator output needs to go all the back to battery side of the switch. Then run wire from the other side of the switch back up to power everything. The way it is now when you flip the disconnect the car will remain running because the alternate will not have been taken out of the circuit.

NSS or clutch safety switch?

I posted the way I do them because it doesn't bypass a bunch of stuff, require splicing and hacking the factory wiring harness. Your current method is a mess IMO with splicing/hacking... You can take a very simple deal and turn it into a wiring clusterf*ck REALLY fast.

I still don't get the fascination with the extra junction lug. Putting additional failure points in your charge line. Run that MSD off the factory starter relay lug and bring a large enough gauge wire forward to supply it with minimal voltage drop.

Is that solenoid mounted to the aluminum on your battery box grounded?

If you don't care about cutting up your harness, have at it.

Those latching solenoids/CD relays are the same type of deal I use for the alt line!