I tried to revive an old thread, but for some reason it wouldn't let me do it.

Basically, I'm trapping over 135mph, and I want to get legal for it, so I need a master cutoff switch (SFWD).

I still have the battery in the engine bay (and I'd really like to leave it there). I am trying to find a good way to wire the master cutoff switch to the rear of the car without relocating the battery.

I read in an old thread that one guy wired the switch to be inline with the power wire of his ignition box. Would that be legal? Would it create a voltage drop/increased resistance/something like that to distrub the effectiveness of the ignition system?

What about those people who don't have an ignition box that allows for this?

 

the master cut off switch has to cut off all power to the entire car. if you just cut the ignition's power, you will still have power to the fuel pump and anything else that is electronic, and in the event of an accident, that would be a fire hazard...

Mike...

 

Interesting...

the rulebook says that "The cutoff switch must be connected to the positive side of the electrical system and must stop all electrical functions, including magneto ignition."

So, if a switch was installed inline with the battery cable, would that stop all electrical functions? Would the alternator keep the system chared to keep it running?

If that is sufficient, then is the only options to 1) relocate the battery or 2) run large-gauge battery wire from the battery (under the hood) to the back of the car and then all the way back to the battery?

 

what you do is re wire the alternator to run directly to the battery, rather than to (on a civic and most other if not all other cars) the cars electrical system at the fuse box... Its alot easyer than it sounds... this way the alternator will supply current to the battery, but not to the electrical system so when the power is cut from the battery to the electrical system, the alternator is not keeping the electrical system going...

Mike...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by servion &raquo;</TD></TR><TR><TD CLASS="quote">
If that is sufficient, then is the only options to 1) relocate the battery or 2) run large-gauge battery wire from the battery (under the hood) to the back of the car and then all the way back to the battery?
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I havn't had any expience re-wiring the alternator like described above, but it sounds like it would work. I will share my own personal experience though with the rear mounted kill switch. First I tried to leave the battery in the engine bay. I ran a #4 welding cable from the positive on the battery to the switch, then back to engine bay for the fuse box and starter. Well, the car would start, but die almost right away and the battery was draining in a matter of seconds. I relocated the battery to the truck and re-did the wiring, and the car ran fine. Since there was 1/2 the amount of cable being used, I concluded that the excess cable was causing the voltage drop. Just something to consider...

 

I am using a continuous duty 12vdc solenoid. So far it has worked well. You can purchase these at your local parts stores. My cutoff switch kills the power to the solenoid and in turn disconnects the battery from everything.