Cut-Off Switches:

[MB] "I think to be truly legal for tech events (like NHRA) the cutoff switch needs to be installed on the positive side of the battery. Furthermore, unless you pay attention to how you wire up the alternator, if you flip the switch when the engine is running, the engine can stay running due to the alternator supplying power to the coil.

So the solution is to route the positive battery cable to one side (call it the +) of the cutoff switch. And wire the big alternator feed wire to the same post (the + side) of the cutoff switch. Then run all power for the car from the other post (the - side) of the cutoff switch to power everything in the car. Wire the polyfuse up to the + side of the cutoff switch and I think you will be set as far as keeping power to your computer.

NHRA say you install cut-off switch in '+' side of battery power or you might not run car at track! This is what I meant when I said you have to properly wire the alternator output through the cutoff switch or the alternator will keep the car running. Of course, depending on what you plan to do with the car, passing NHRA tech may or may not be an issue. Most cobras can't legally pass tech anyway due to their rollbar design. I assume FFR instructs you to wire it up through the '-' side because it is a simpler way to go."

[65] "When putting in your cutoff switch, make sure you run a "keep alive" (always hot) wire to the computer. If not, it will always reset when turned off. I would definitely switch the positive side. Wouldn't want to take a chance of blowing the EEC-IV."

The idea of the switch is to quickly remove (for any reason) the BATTERY from the circuit. If the -BAT is tied to the frame and the engine is grounded to the frame, then the engine will be self-sustaining if it has a working alternator. The BATTERY remains connected for two reasons: To recharge and to help smooth out AC waves put out by the AC to DC rectifiers.

Take a closer look at the wiring diagram for the Starter Solenoid is. There you can see that the battery can be removed because the ALT+ would provide enough juice to run the entire car. The terminal SOLENOID1 has the two wires that run to the starter, while SOLENOID2 has the +BAT, +ALT, +ECC, +TERM (Fuse panel), and even some lines for the Defrost and Power seats.

In theory once the car is started one could remove the battery completely and the car will remain alive. The Battery's main purpose is to be a repository of energy and provide a source of juice to START the car and to keep the computer juiced until the next run cycle.

Therefore, the idea of the switch is to remove the +BAT (or huge WELDING CABLE) from the circuit in case of accidents or any maintenance."

Remote Terminals:

[BS] "I'll be installing mine in the lower left hand corner of the trunk, just where the pan drops off. Why, because I want the cables routed away from the fuel lines, and will still have them within reach if I ever need to have the car jump started, just pop the trunk lid, and away I could go........The battery cut off that was originally installed in 2134 did not have a removable key, so I may end up replacing it with one that does for added security and peace of mind as well...."

[D55] "My only fear of having the remotes mounted externally is that some jackass (or meanspirited BASTARD) could easily short out your little Cobra while you're slurping ice cream cones and walking around the car show. (Marshmallows anyone?) I think the external mounting makes the car look like it just came off a track, but I'd rather have them locked up in the trunk."

[DP] "If the remote battery terminals are external it would make sense to wire the positive terminal to the load side of the existing battery disconnect switch. With the battery switch "off", the positive remote terminal is not connected to the battery. That would seem the safest way to prevent potential problems associated with the exposed terminals"

[D55] "OK, that would work as long as you put the positive remote "aft" of the battery cut-off (opposite the "hot" side of the cut-off) and, as dpmac stated, you've got the battery cut off set up to cut positive. My cut-off is run from the negative side (which I guess I'll never hear the end of at this point, although my FFR instructions TOLD ME to hook up the disconnect to ground and not positive), my remote terminals are happily in my trunk (and spaced quite a bit apart from each other to avoid jumper cables from shorting on each other)."

[IL] "I separated them, one on the far left, one on the far right (positive). For the positive, I glued black rubber on the aluminum surrounding it for several inches so that I won't accidentally touch ground with the leads. When my battery disconnect switch is off, nothing is connected to it except for a fused separate line to my alarm system. This way, the alarm still works if someone turns off the battery power. I have both my battery switch, and my fire bottle pull right down low next on the left side of the passenger seat - you have to look for them to find them. I leave a pin in the fire bottle in the trunk when not on the track to avoid any tamperers for making a mess."

[AL] "Remote terms inside trunk, lower left side next to fuel cutoff. Cutoff switch located behind driver seat next to tunnel. Not really visable. Read somewhere that some racing sanctions want them visable, like even outside the car for easy access by track crews etc, which mine aren't. Also used poly fuse across the cutoff terms to keep the computer alive. Would also recommend a cutoff switch between the battery and remotes terms. During the build there were times that I would have liked to kill those posts also."

[Wade] "I put mine inside the trunk, out of the way. So far, I have never needed to use them, and I hope I never do."

[NA] "I have mine in the engine compartment mounted to an angle bracket attached to the rear of the front X-frame member on the right side. Not hard to get to - plus during the winter months I can connect the trickle charger leads from underneath the front suspension, and still have the hood, trunk, and doors closed. One gauge wire from battery to the terminal and then 4 gauge (kit) to the starter solenoid. Battery connected to frame at rear end with one gauge wire, and at terminal another grounding connection with 4 gauge. Works for me - no cutoff switch, don't drag race - don't need it!"

[D55] "IMHYSO (In My Humble Yet Sarcastic Opinion) I can't see why you'd mount "remote" (as in "away", "far", or "distant") terminals "near" the solenoid. You have a looong hot terminal coming right from the battery to the hot side of the solenoid. You can hook a jumper to the hot side of the solenoid and ground anywhere you please and crank away. The trunk/outside rear makes the hook up convenient."

[MC] "I don't know if it a good practice or not but if you ever need to jump start a car and I have done this even on a semi truck is to simply place one of the jumpers on the starter positive terminal and the ground to the engine block and wala. now to make it easier place a terminal inside the engine compartment somewhere easier to get to than the starter and run a line down to the starter, or simply mount the starter solenoid somewhere easy to get to and this would accomplish the same thing, yes no maybe I think this would be better or just as good since your putting power right where you need it considering the battery is at the opposite end of the car with a lot of cable from point a to b. my two cents save the money and extra work and do something else with it."

[DP] "

I have mounted the RBT's in the trunk at what appears to be standard location as noted in Wades Picture above. I have connected the Red terminal direct to the positive battery post BEFORE the battery cut off switch. In this fashion I can charge the battery with the cut-off switch "off", key removed. If I need to jump start the car, that would require battery switch "On" or the key in anyway.

Rather than using the Raychem polyfuse I ran two 16awg leads from cut off switch to the under dash area that will connect to a basic marine small 1 Amp push button circuit breaker. This will keep the computer powered up. Should there be a problem, or screw up on my part the breaker will trip and I will have to press the small button under the dash to reset it.

The poyfuse resets auto. If there is a short circuit or load greater than the polyfuse rating, I assume it may keep tripping/resetting until??? I would feel better if I had to do the reset, this way I would always know something was up."

Battery Fell Out!

[JP] "My battery fell out of the rear of my Cobra after a bit of hard acceleration today. I dragged it a few blocks by the cables before realizing what happened, and had to be towed to a local station for repair. I found the battery tray and three of the threaded hook rods that hold everything to the frame; nothing failed, unless maybe I broke the fourth rod somewhere else. I believe it's my fault whatever happened, I haven't checked the tightness of those nuts for a long time. I will regularly in the future.

I could've had a real disaster: my cables were long enough to allow the battery to drag back under the gas tank. With no rubber tank cover, the + and - posts would've certainly contacted the tank metal...ka-boom. Probably all kinds of other mischief that could've happened. SOOOO...CHECK YOUR NUTS RIGHT NOW, please.

Does someone have a better way to mount the battery, to avoid this possibility in the future? I'd like to leave the battery down there, but have no ideas how to secure it better. Thanks for any suggestions!"

[DI] "you possibly double nut the hook rods or use some sort of self locking nuts (the type that have the teflon in side that make it near impossible for them to loosen up on their own). Maybe some locktite as well"

[RT] "the kit comes with nyloc nut's, they should not back off unless they have been reused a few times.  Double nutting would be the easiest fix."

[LS} "I was under my car yesterday and noticed that the battery tray was loose and I could rock the battery back and forth a couple of inches. It's on my list to secure it more safely."

[RS] "Several times each year I like to run an open track event. The Cobra goes up on stands or a hoist prior to the event. Every fastner gets a wrench or a socket, not to mention oil, brake fluid changes and a thorough visual inspection. Take the time to check things out. I like the battery location because it's down low and cheap to replace every couple years."

[RG] "I took a slightly different approach. I fabled up a battery box that surrounds the battery, but is still open at the top (no way for the battery to come out unless all the nuts come off). Now the potential down side, I bolted it straight up thru the tubing into the trunk, so you can see the nuts on the floor of the trunk. But I feel much better about it in this location. I also went with an optima battery. I know it will be a pain to change out, but I don't expect to be doing it that often anyway.

The other option is to do the remote location of the whole battery into the trunk."

[RB] "Every time I'm doing my check over I have been checking those bolts as well as the tightness of the actual battery terminals. I have heavy rubber covers over the battery terminals - got them sometime ago incase the battery did move around. I can see how if the battery moved the rods would be looser. So maybe a wooden frame - between the battery and the bolts - around the outside of the battery would help hold it in place. That way if the battery bolts loosened the battery still would not move - until the bolts came completely out."

[DK] "1. Nothch the hooks so they are less prone to slip out of the frame holes.

2. Add aluminim tubes over the rods. With a few washers for shimming, I should be able to torque the rods and all the stress will be taken up against the frame not the thin battery tray."

[HD] "I relocated my battery up front. May not be period correct, but sure easy to get to for service, inspection, etc."

[FFR] "We have a battery box kit that locates the battery in the trunk for the irs guys but you could easily use this if you are concerned.

I really like the tubing around the bolt idea since it allows you to tighten the nuts tighter. I think I will put out a tech bulletin about this one since it could be dangerous if those nuts are not tightened properly.

Better yet I think I will put the tubing in the bulletin so people actually use it."

[RO] "Most hardware stores carry aluminum angle, put a length on each side under the tray to add more rigidity. We always double nut the assembly and have also put epoxy in the holes on the frame so the hooks are more permanent. The box in the trunk is easy but eats up room."

[FS] "I almost had the same thing happen to me at NERC this past summer.  When I got home and jacked the car up to clean it up and go over everything after two days of open track I noticed the battery hanging by only three of the four bolts.  I think the main problem is where the "J" bolts hook into the 3/4" tubing. No matter how tight you make them they can still come out of the frame. The tubing idea should work. But I think you should run 1/4-20 bolts through the 3/4" tubing and then fabricate new battery tray bolts that can be bolted to the 1/4-20 bolts and to the battery tray. This would positively lock the battery in."

[JP] "Double lock-nutted the threaded rods today with big flat washers underneath, so think I'm set for the time being."

[MR] "I bent the hooks further past 90 degrees so they would not be able to slide out of the holes so easily. Also put 1" square rubber pads between the tray and the battery, and the battery and the frame to prevent things from sliding all around.
Also, I've been thinking of offering a powder coated stainless steel tray that has edges folded up on all 4 sides to add stiffness in the long dimension. Anybody interested in such a product? Not sure it solves the falling out problem but it might be part of it.
There's always our behind the passenger seat mounting kit, but that is only for original build solid axle coil over people."

[BR] "Close call! I had a friend weld a new tray from 1" angle. I'll take a pic and try to post it here. It sits on top of the x member that comes with IRS. We also had to cut a panel from the trunk skin and fab. a new piece to become a cover. This frees up the trunk space and puts the bat. down low. the new Bat. box is bolted to the frame with 5/16 bolts and nylocked. the battery itself is held in by a clamp at the base just as like the donor."

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