Master Shut Off Switch

Sandy · 08-11-08, 03:32 PM

This has come up before, but it's quite here today so I'll bring it up again ;-)

Who has shots of master power switches on their 40's? I was looking at doing a remote OFF (Off only from outside) like some of the newer cars do with a cable pull. Anyone rig one of them up?

I was almost thing of moving it to the front of the car near the windshield cowl area (if I can call it that). Will make routing cables very easy and clean.

Sandy

Dutton · 08-11-08, 04:22 PM

Sandy,

From a corner workers perspective, the location is perfect. Your friends in white thank you.

T.

Scott Calabro · 08-11-08, 05:39 PM

Hi Sandy,

Why do you want it soley remotely activated from the exterior?

Is this a track/scrutineer requirement?

To me the attached simple wiring diagram(or your modification thereof) is really the best way, barring any sanctioning body requirements of course.

It is just a simple idea only, and is of no connection to TSC.
(Disclaimer for the ambulance chasers out there)

You could even install a "G" switch in "series" to shut off power in the event of an off.

Just a thought.

Cheers,
Scott

Sandy · 08-11-08, 06:39 PM

I have a similar concept right now except for the main power to the starter. The rest of the power to all other parts of the car are run via a master relay and that control is on the dash. So semi' master switch if you will but will kill anything except the starter main power to the starter solenoid which nothing else will be connected to.

The external master is for safety workers and will really cut it all off in the event of the driver not being able to. Will figure a way for the driver to also have access to the mechanical master, may be like a fire system pull cable, just depends on where I stuff the mechanical switch (think flaming river master with a cable pull but not sure).

Also forgot the Inertia switch can be easily integrated into the works since the master power of the car is relay driven. Just need to think if I want to shut of ALL power or just fuel/ignition, I'm guessing the latter.

What's TSC?

Sandy

Scott Calabro · 08-11-08, 06:54 PM

Sandy,

TSC = Tornado Sports Cars inc.

If you think about it the "G" switch is better than the one accessible to the track workers as its instantaneous, although probably would not be accepted for whatever reasons.

Really if you want to go top shelf put both a mechanically activated relay in series before the remote electrically activated one, inside a nice "junction/relay box"

This way all the bases are covered.

Cheers,
S

Jac Mac · 08-11-08, 08:09 PM

Quote:

Originally Posted by Scott Calabro

Sandy,

TSC = Tornado Sports Cars inc.

Cheers,
S

Gee, and all this time I thought it was: Tornado Scott Calabro, (strictly in relation to kit building speed & not necessarily to any other hidden talents

.

Small apologies for thread drift Sandy!!!

Scott Calabro · 08-11-08, 08:11 PM

Too funny Jac!

Sandy · 08-11-08, 09:16 PM

No apologies for the drift any Jac-SMACK is worth it!

I was looking at the electronic type of master switched, but they are too costly and when all said and done not as good as a solid mechanical one (IMO). Since the battery is up front, closer to the battery is a better bet for me.

Anyone with pics of batter cut off's on the cars?

Sandy

Ron Earp · 08-11-08, 09:45 PM

Hey Sandy,

you can simply use two master switches in series. One accessible outside, one on the dash. I wired the Jensen like this which meets SCCA specs and was convenient. That way I could turn that death trap off.

My 260Z is not wired like this, only one master accessible from outside but that will change.

Ron

Rob · 08-11-08, 09:47 PM

Here's mine Sandy...... Hella #HLA-002843011

Ross Nicol · 08-12-08, 12:06 AM

My switch turns off all the electrics, bar the battery to starter circuit. Of course the starter will not crank because the solenoid circuit has no power. In the photo you should be able to see a black cable that comes from the pull ring where the RH filler would be if I had a tank on that side.The scrutineers who check my car quite often make start the engine so they can pull the ring to check if the engine stops.I believe this setup follows the 'kiss' principle Sandy and I reckon simplicity is the key to reliability in a race car. What's this 'G' spot Scott is reffering to?
Ross

David Morton · 08-12-08, 10:34 AM

This is my set up with the switch above the battery so least cable run, and a bowden cable to operate it in the cab. It's accessible from outside via the left lower air intake - the switch sits their visible in the centre of the intake and a lable pointing to it as well:

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Big-Foot · 08-12-08, 10:45 AM

Quote:

Originally Posted by David Morton

This is my set up with the switch above the battery so least cable run, and a bowden cable to operate it in the cab. It's accessible from outside via the left lower air intake - the switch sits their visible in the centre of the intake and a lable pointing to it as well:

First off - just shy of a bazillion dollars worth of AN fittings there... BLING!!!

(nice bling though)....

I like the switch placement.. I've used a number of those very same switches and they seem to work fine. I also use multiple switches in series so there is one on the outside for the workers and one inside for me.

Just a thought.. Since that switch flag must be rotate clockwise to arm the system, one could easily run a braided wire tether to the switch flag through the bulkhead to the interior where you could have an "Emergency PULL" handle connected..
Now you've killed two birds with the same stone.

CRASH33 · 08-12-08, 12:29 PM

I have been using 200 Amp continuous duty relays that I got from Grainger for a remote master kill. I've only experienced one failure were I was trying to refire a hot engine for a loooonnnggg time without success. This setup allows a termination almost right at the battery for EVERYTHING. NASCAR officials also wanted me to install a typical manual switch in the quarter window area. The relay cost about $12 if memory serves. I bought a few of them about 6 years ago. Don't know if the price has changed or if they are even still available.

BTW- I use the negative side of solenoid leads for the activation swich so NO power goes into the driver area.

David Morton · 08-12-08, 08:14 PM

Randy,
yes - the other end of the cable you can just see on the red part of the switch has a PULL TO OFF inside the cab. I thought of arranging it so I could have a PULL TO ON as well, as I always forget it when I try to start the engine and have to get out of the car again to remake the switch.
Sort of being a bit decadent really.
All the AN fittings were from Earls Speed Shop just north of Longbeach and didn't cost all that much really. They did everything from the Weber connections, Fire extinguisher pipes to the Oil hose to the thermostat and cooler, and quite a few that are out of sight as well such as a fuel feed.

Dutton · 08-12-08, 09:52 PM

Guys,

I'm not the most experienced corner worker I know but, after 20 years, I have managed to be around for a few things that we all know sometimes happen while on track.

When the master switch is turned to the off position, please be sure the ground circuit is open. No ground, no spark source. Cables can get pinched in a heavy impact and, if the cut in the insulation is in the wrong spot, well, you can imagine the possibilities.

T.

Sandy · 08-12-08, 09:54 PM

David that is exactly what I'm thinking, simple, and dual purpose (inside,outside). Ross, I think think that I am wiring up the same way. That is how my mustang and cobra are set up. 'G' Spot, well isn't that the aluminum motor in the back of my car

I'm not too keen on using relays for the stater master power, I think the mechancal switch is pretty solid, but I like the idea of cutting the ground and running only that cable into the car. I'll have the battery in the footwell so it is a wash for me, but excellent idea, I always hated the roll bar mounted switch, seems like that is a nice place to start an electrical fire with all the extra cables and connections needed.

I have a spare Flaming river switch that I'll try to use if it will fit, I'm also not a fan of the red/black plastic switches, everyone uses them, they just seems a bit on the flimsy side. The Flaming River switch is also spring loaded which might also work great with the cable.

Thanks for all the input, and pics of the mounting. BTW who makes the Red cable Pull handles? I don't think I have seen them at Pegasus or other places? Is it just a red cover over the wire tied up?

Sandy