Master Cutoff placement on s13

[Driftaholic84]

The Formula D 2018 rulebook says:
MASTER CUTOFF
A. A Master electrical cutoff switch, wired to completely shut off all engine and electrical system function except for electrically operated fire suppression systems is mandatory and must mounted outside the vehicle, on the right side cowl just below the windshield and is to be clearly marked with the appropriate “OFF” markings.
B. The electrical terminals of the cut-off switch and/or any relays used in the circuit must be sufficiently insulated

There isn’t a whole lot of room there on a s13. What is everyone doing? I talked to one of the guys at Enjuku and they mentioned something about a pull cable? Does anyone have a picture, or a link to what people are doing for this? I have looked around for a couple of days now in my spare time and haven’t really found a solid answer yet.

[tuzzio]

Are you participating in Formula D? If not, I really wouldn't worry about it.

[hanzbrady]

You'd have to gut the factory wiper assembly to properly fit it exactly where they state however you can probably get away with something like this.

Post #676

http://zilvia.net/f/showthread.php?t=414137&page=23

However if you are building an FD car I'd recommend just going to an aftermarket single wiper arm and gutting the factory cowl.

[oLemurs]

is all this due to that dumb ferarri guy?

[hanzbrady]

Originally Posted by oLemurs

is all this due to that dumb ferarri guy?

No, the battery cut off rule has been in place since FD was conceived. This is common practice in SCCA which is the tech rule book FD was based off.

The switch needs to be accessible to the track crew in the event that the driver is imobile or unconscious so that they can shut the car off to stop it pumping fuel or running on track during a rescue.

[Driftaholic84]

So I have been doing a little more digging.. some of these are hard to see and you can’t really see how a couple are mounted. Here are a few different styles I have been able to find though..

It would appear that this is the key type that I have ( 6-pole, w/ alternator protection) and it also appears that the owner has retained use of the factory wipers as well as the panel itself.

This one seems to have eliminated that cowl trim but still has factory wipers? (I can’t really see the motor in there) It doesn’t seem to be the cleanest installation either. (Sorry if it’s your whip, but you know it’s kinda sloppy :/ )

This appears to have a pull cord as described by Enjuku? Idk if it’s for fire suppression, or a master cutoff I can’t tell from the picture. I also haven’t really looked for a pull cord yet.

This one appears to be a knob? I haven’t been able to find one like this, although I have seen two now including this one. The other in red.

So this all started out as me fixing the mistakes and poor workmanship from the last owner. Amongst other things that I didn’t feel were adequately installed on this vehicle when I got it, was a battery relocation. They had everything running to a single terminal power distribution block, that had no sort of weatherproofing on it & was screwed to the top of the lower frame rail on the passenger side. They obviously had cut the oem connectors off and had ring terminals at the ends of all of the wire, going to the single post on the distribution block. They also had run a 2ga wire directly from the power distribution block to the alternator, along with the oem wire. From that single post, they had run a piece of 2ga to the battery. The other side of the battery, was grounded to the rear passenger shock tower. The huge interstate battery was then slapped into a topless, plastic “battery box” w/ no sort of tie down holding it in. The plastic box was held in with one screw on the side of the box, going into the sheet metal frame.

You can see why all of this had to go.. I did a little searching and I think I have what I need figured out and here for the most part. At this point, I have ordered:
-25’ of 1/0 gauge welding cable
-25’ 1/2” braided loom
-100’ 1/4” braided loom
-20x 1/0ga gold plated ring terminals w/ red and black sleeves (I got them today and they look crappy I am thinking about ordering new ones and returning these)
-2x cased, gold plated battery terminals
-Bussman 100amp type III circuit breaker (got it today as well. Kind of looks cheap, wondering if there is better options)
-scorpion 0,2,4,8ga covered gold power distribution block w/ digital readout
-key type, 6-pole cutoff switch with alternator protection
-Eddie Motorsports aluminum battery tie down for Optima 34 series
-Optima yellow top

I also had a question about how I should wire in the switch with the distribution block. Now after reading the rules do I have to wire everything to the cutoff switch, or can I wire everything to distribution block,then from the block,to the circuit breaker, to the cutoff switch, to the battery? Should I just use the cutoff switch as a distribution block, being that it’s got alternator protection? I still don’t know how I feel about that. What do you guys think?

[Kingtal0n]

why can't it go in the back? Isnt it harder to get to under the hood? How are you going to get to a switch on a flipped upside down car under the hood. It should be on the back? Am I missing something?

[Driftaholic84]

Kingtalon I completely agree with you.
It isn’t under the hood. It is on the lower cowl under the windshield. If it has to be placed under the hood because of spacing issues, I am told that a pull cord that is accessible from the same area, is adequate.

[Driftaholic84]

I also was thinking about adding another switch that is driver accessible from within the cockpit. I feel like that should be in their rule book as well. I’d like to think that in certain scenarios, that I could get to the cutoff before them anyways. So, the wiring would go battery >drivers cutoff>exterior cutoff >100amp circuit breaker >power distribution block >out to starter, alternator etc. this all sounds correct, right?

[DJPimpFlex]

Pro tip. Just buy this. You can place it wherever you want and run small tiny wires to a switch anywhere you want.

https://www.waytekwire.com/item/4440...ry-Disconnect/

Pic of my kill switch.

[hanzbrady]

Originally Posted by DJPimpFlex

Pro tip. Just buy this. You can place it wherever you want and run small tiny wires to a switch anywhere you want.

https://www.waytekwire.com/item/4440...ry-Disconnect/

Pic of my kill switch.

I was looking for this and gave up halfway through your thread lol.

Yes this is FD legal.

Source: He ran FD in that car.

[Kingtal0n]

Originally Posted by hanzbrady

I was looking for this and gave up halfway through your thread lol.

Yes this is FD legal.

Source: He ran FD in that car.

What even is this? All I see is a little black circle with a brass ring. It doesn't look like a switch?!

[TheRealSy90]

Originally Posted by Kingtal0n

What even is this? All I see is a little black circle with a brass ring. It doesn't look like a switch?!

It’s the trigger button for the solid state isolator. Push it and it disconnects power like the kill switch.


Sent from my iPhone using Tapatalk

[Driftaholic84]

Is that formula d legal?

[Driftaholic84]

Could I use this to run two? One inside and one out? Do I need the 300a or would the 200a be ok?

[TheRealSy90]

Cartek makes a sick solid state isolator kit.
https://www.moreheadspeedworks.com/p...tery-isolator/


Sent from my iPhone using Tapatalk

[Driftaholic84]

That cartek unit is dope. The picture he posted is a push button that he’s used as a cut off switch. It’s attached to the unit he posted in the link.
DJPimpflex, what are you doing for a power distribution block?

[DJPimpFlex]

Yes FD legal. Very safe and awesome. I use a bussman relay box. Power goes from battery to starter to kill switch then to solid state isolator. When you push the button it kills the entire fuse box (ignition, fuel pump, etc.). You could use this to run as many switches as you want but I only run 1 as I have the main ignition switch in drivers reach. You could use a solid state PDM as well but I haven't upgraded to that yet. The mini relays and breakers are reliable and easy to use.

[Driftaholic84]

I am not quite looking to redo the whole harness with this motor, but I like that setup. The installation looks really nice. I’ve been thinking about this cartek solid state isolator. Has anyone here installed one? Would I need a breaker between the alternator/starter/vehicle electrical systems and the battery? What about on the other side of the battery going to the battery isolator?

[TheRealSy90]

I don't see the point of an additional circuit breaker if you have an isolator but that's just me and I know nothing.
I wanted to add that there IS enough room to install the traditional style cutoff switch at the passenger (right) wiper cowl. As long as all of the HVAC components are removed under the dash. I have mine currently mounted there and can add photos later after work.

[Driftaholic84]

I found the installation manual and it looks pretty straightforward. I think I am going to order one in the morning. This diagram made a lot more sense to me than the other as far as installation for our application as well.