[RESOLVED] Battery relocate/kill switch questions (road course)

[turbosax2]

I'm going to relocate my battery to the trunk and I want to make sure I'm compatible with road racing rules. The NASA CCR states:

The battery shall be securely fastened down to the car. No Bungee cords or rubber
cords may be used to function as the sole hold down mechanism. An electrically nonconductive
material must cover the positive battery terminal. Any battery located inside
the driver’s compartment shall be fully covered and firmly secured to the chassis in a
marine type battery case. True dry cell batteries may be mounted without a surrounding
case, however a case is still recommended. Note- there is a difference between “dry
cells” and “gel cells.” Gel cells still need to be mounted in a case.

By marine type battery case do they specifically want a plastic one like this or would a metal one like this be acceptable?


And for a kill switch I was planning on putting it in the rear so I can pass inspection at a drag strip (since I want to do all types of racing). But the CCR says:

An electrical master switch is recommended on all cars, and required on some, as listed
in the class rules. It shall be mounted so that it is easily accessible from the outside. If
mounted outside the cockpit, it should be mounted in an area where it is least likely to be
damage (e.g. cowling near wipers). The switch shall cut all power except to the onboard
fire system and any other life support / medical device. The switch location must
be clearly marked. Any marked switch must function as per this rule, or the indication
decal must be removed.

Would the switch in the rear still be acceptable? I researched some and found that most cars have them near the front windows, either inside the car mounted to a roll cage (which I don't have) or outside the car in that area. Like I said, I want to be compatible for both drag and road racing, so would the rear be acceptable for road racing too as long as it's properly labeled? I'm just concerned they might consider the rear of the car an easily damaged spot.

Anybody have any insight? I don't plan on racing competitively any time soon, just doing HPDE's and autox sort of things, if that changes anything or means they're more lenient with the rules. But I still want to be legal and safe.

 

[Ludachris]

I'm sure this is going to be dependent on how your region handles it, but if you're not racing, you probably won't have any issues with it being in the back. I don't. Check with your regional HPDE Director just to be sure. When you step up to racing, you might have to install a second switch up to the left of the steering wheel so that it's accessible from outside the driver's door. Just make sure it cuts power to the alternator as well as the battery - the drag strip tested my switch only to find that it didn't cut alternator power. They let me run anyway.

I use a blue Moroso plastic box, which is basically the same as the red Summit box that is now available.

 

[MIdsm]

You could also use a continuous duty high amperage relay like some of these:

relays continuous duty 12 volt & 24 volt DC power relays,starter relays

RV Powerhouse - A Powerful Selection of Quality RV and Marine Parts

Wire Terminals, Automotive Wire, Battery Terminals & Electrical Supplies


The relay would be energized through multiple switches in series - one in the back, one next to driver and possibly one up front. The remote (away from the driver) switches could be removed when not at the track.

A 200A relay ought to be enough.

Good luck.

 

[turbosax2]

I thought about using a relay system too. However, I don't think you can use that type of switch in the rear for drag racing. Plastic and keyed switches are prohibited, and I remember reading somewhere that a relay system like that was not allowed either. That might work for a 2nd switch up front, but I'm not sure how one would wire that so both switches act independent of each other to kill power.

If I'll be fine just having one switch in the rear for now then I'm happy with that. If/when I ever race competitively then I can worry about adding a switch up front. I just don't want to have a switch in the rear, go to a racing event and not pass inspection because I have that switch. I'll try to get in contact with some local officials to see what they say. If anyone else has advice please share!

 

[Ludachris]

I thought about using a relay system too. However, I don't think you can use that type of switch in the rear for drag racing. Plastic and keyed switches are prohibited, and I remember reading somewhere that a relay system like that was not allowed either. That might work for a 2nd switch up front, but I'm not sure how one would wire that so both switches act independent of each other to kill power.

If I'll be fine just having one switch in the rear for now then I'm happy with that. If/when I ever race competitively then I can worry about adding a switch up front. I just don't want to have a switch in the rear, go to a racing event and not pass inspection because I have that switch. I'll try to get in contact with some local officials to see what they say. If anyone else has advice please share!

Yeah, I'd just cross that bridge when you come to it. But still do ask your regional NASA Race Director for their recommendations.

 

[turbosax2]

I sent emails to both the Mid-Atlantic and Northeast regions of NASA yesterday. Awaiting responses.

 

[turbosax2]

Got a response from Mid-Atlantic:

Eric, either battery box would be ok. The kill switch will be ok where you state, if it is for drag race specs. For road race I would rather see it mounted where the driver could reach it while strapped in, but there is no rule for that. Richard

Edit:
And from Northeast:

Eric,
Either box is acceptable. The kill switch can be located anywhere it is visible to a safety worker and clearly marked.
Joe Casella, Dir.

 

[KGB Pilot125]

is it feasible to run 2 kill switches?

 

[tenn-gsx]

If you put them in series then either one would be able to kill power regardless.

 

[1Gdsmdriver]

not to jack the thread, but i am setting up my car for racing and was looking at the remote relay set up for my car, is there a reason why that one would not be allowed

 

[4pistons]

Here's a suggestion for a rugged battery box - surplus ammo boxes. Armygear.net -- Ammo Can: S.A.W. Box, GOOD CONDITION That particular one is large enough for a normal battery, has a sealed flip-top lid, is heavy duty steel, and is only $11. I grabbed two of them at a local gun show for $10 each.
There are many different sizes depending on the ammo they held. The S.A.W. ammo cans measure 11.75"L x 6.75"W x 8.25"D on the inside. (S.A.W. is 'Service Automatic Weapon')
You'd need to drill and grommet two holes for the cables and bolt it securely to the floor. You'd also want to run a vent hose to the outside of the car, too.

Rick - '91 GSX - Armed & Dangerous!

 

[knochgoon24]

Eric,

Did you get this setup completed? I now have my battery in the trunk and need to get a kill switch setup before I can race next month. My confusion is with how to kill the alternator.

And do you need a box even with the Red Top since it's sealed? There aren't even vents on it.


EDIT: Ok. After some more searching, I think I found that I shouldn't kill the alternator power, I should just kill the fuel pump power. That should be much easier.
I'm still curious about the Optima Box.

 

[turbosax2]

Yes, it's complete.
http://www.dsmtuners.com/forums/han...-relocation-project-log-12.html#post152022910

Wire the alternator straight to the battery side of the kill switch (with an inline fuse). I don't believe the Optima would need a box (especially in autox) but I wasn't taking any chances.

 

[snowborder714]

EDIT: Ok. After some more searching, I think I found that I shouldn't kill the alternator power, I should just kill the fuel pump power. That should be much easier.
I'm still curious about the Optima Box.

Did you find a definitive answer as to why to kill the fuel pump over the alternator? I've read it's another option, but typically the alternator is killed. I believe when we rewire Eric's pump that we might add the pump to the switch as well. At least we've talked about that in the past.


SCCA rules for battery.

Any wet-cell battery moved from the manufacturer’s original location
shall be in a non-conductive, marine-type container or equivalent
and the “hot” terminal shall be insulated. All batteries (on-board
power supplies) shall be attached securely to the frame or chassis
structure independent of the marine-type container. NOTE: This will
allow the use of gel cell or dry cell (AGM) batteries without a nonconductive,
marine-type container where applicable.

Based off of those rules and the NASA rules Eric included in the first post, because Optima batteries are dry cells, you don't need a box.

If you had a gel cell battery and ran in NASA, you would need a box, even though in SCCA you would not.

 

[knochgoon24]

Did you find a definitive answer as to why to kill the fuel pump over the alternator? I've read it's another option, but typically the alternator is killed. I believe when we rewire Eric's pump that we might add the pump to the switch as well. At least we've talked about that in the past.

People just suggested killing the fuel pump, because it will shut the car off in 2-3 seconds, just like killing the the alternator.

Since the fuel pump is already in the back, and only takes 10ga wire, it's easier (and cheaper) to run it to the kill switch.

There has also been mention of electrical feedback when killing the alternator.

 

[snowborder714]

it will shut the car off in 2-3 seconds

I think this was the reason we didn't use that as Eric's main kill option. That would be enough time to feed more fuel into a fire if one had already started.

FWIW, Eric's car dies instantly when you flip his switch.



And I don't remember reading anything about electrical feedback when dealing with the alternator. Do you happen to have any links to this?

 

[turbosax2]

People just suggested killing the fuel pump, because it will shut the car off in 2-3 seconds, just like killing the the alternator.

Since the fuel pump is already in the back, and only takes 10ga wire, it's easier (and cheaper) to run it to the kill switch.

There has also been mention of electrical feedback when killing the alternator.

Electrical feedback is a concern. However, it is not a problem since I wired the alternator to the battery side of the kill switch. Had I wired the alternator to the other side of the switch, the car would continue to run when the switch was flipped. (But the car would not be able to start again once shut down, because the starter has no power.)

I used the alternator rather than the fuel pump to kill the car because of that time delay. However, I do plan on wiring the fuel pump to the switch when I get around to rewiring it. Mostly because it's the easiest way for me to rewire it with my setup.

 

[knochgoon24]

I don't think that it would fuel a fire any more than killing the alternator though. The pump immediately gets shut off either way, so no more fuel is being forced through the line. It actually might be a better idea to burn the extra pressure from the fuel lines inside the engine instead of outside it.

And it's definitely a lot cheaper, easier, and lighter than running another power cable from the alternator back. It's also that much less wire to risk shorting.

I had read the 2-3 seconds on some other car forum while searching how to wire in a kill switch. I'm not sure how long our cars could run on the residual pressure. Probably not for long.

I also found the link for the alternator problem: http://www.flamingriver.com/index.cfm?ptype=article&article_id=22
It says a resistor needs installed??? I'm guessing that's only if you kill the alternator by running the power through the swtich and back into the system with a 4 post kill switch.

 

[MIdsm]

To my understanding, the secondary function of the battery cut-off switch is to prevent any sparks from starting a fire. If the gas tank ruptures during an accident the gas fumes need an ignition source and a pinched/grounded power line may start a fire. Once the battery/alternator get disconnected there is one less possible ignition source giving the driver a few extra seconds to vacate the vehicle. On a side note, the only system connected directly to the battery should be an electrically engaged fire extinguisher system.

 

[knochgoon24]

To my understanding, the secondary function of the battery cut-off switch is to prevent any sparks from starting a fire. If the gas tank ruptures during an accident the gas fumes need an ignition source and a pinched/grounded power line may start a fire. Once the battery/alternator get disconnected there is one less possible ignition source giving the driver a few extra seconds to vacate the vehicle. On a side note, the only system connected directly to the battery should be an electrically engaged fire extinguisher system.

Does that say anything new that hasn't been said?
Forgive me, I don't see the point you were trying to make.

 

[Zmann42087]

I'm considering relocating my battery this summer and was doing some preliminary reading. Having read this thread over, it sounds like a battery kill switch is not even required for, say, NASA HPDE or SCCA Solo-II/autocross? I have no intentions of ever taking my car drag racing, so passing NHRA tech is not an issue.

 

[slamcav]

I actually took my factory battery mounting plate trimmed one corner and welded it to the subframe behind the trans. Used a honda battery and honda tie down. Works like a champ and all the factory cables fit perfect.