Battery Relocation

scramblr

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I have not heard anything but speculation on the track. The current on the way out owners leased the property from a management group and haven't paid their lease payments for 6 months (again rumors) but they make sense since now its closed. Some have tried to say its the city government shutting it down but knowing most of them i doubt that is true, they are all for us gear heads. What i was told was that the plan is to doze the entire property and build apartments which makes sense with the growth happening along ih10.

That would suck....hope someone saves it.
 

kerrynzl

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Your 4 gauge wire from the alternator to the battery is hot at all times. I would connect the alternator to the 1/0 wire at the junction box through a 150 amp continues duty solenoid. This eliminates the 4 gauge wire to the battery. The disconnect would have to be a dual switch to energize/deenergize the solenoid. This would leave no hot wires beyond the main disconnect when it is open.


You leave the charge wire on the Battery side of the Isolator Switch! This prevents the Alt charge backfeeding to the ignition and keeping the Engine running.

But as you observed it remains hot all the time!
The simplest remedy is to add a H/D diode in this wire [close to the battery as possible]
This makes the wire dead as a dodo when trying to discharge the battery, and hot when the Alt is charging the battery.

@ scramblr doesn't need an Isolator switch on the ground strap [a waste of time as the main isolator switch achieves the same result]

If you're wanting a cheap source of Battery Cables ,look at your local "U" Pull for BMW E36's [they have trunk mounted batteries]
 

kerrynzl

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I certainly understand what you're saying. The rules actually state the switch must stop all electrical functions. The above schematic does that by not allowing the engine or any component to run. And I do realize the alt cable is hot at all times, but it still meets the intent of the rules. At least that's how I understand it and if I'm wrong please let me know.


8:4 MASTER CUTOFF Mandatory when battery is relocated, or as outlined in Class Requirements. An electrical power cutoff switch (one only) must be installed on the rearmost part of each vehicle and be easily accessible from outside the car body. This cutoff switch must be connected to the positive side of the electrical system and must stop all electrical functions including magneto ignition. The off position must be clearly indicated with the word “OFF.” If switch is “push/pull” type, “push” must be the action for shutting off the electrical system, “pull” to turn it on. Any rods or cables used to activate the switch must be minimum 1/8-inch diameter. Plastic or keyed switches prohibited. Switches and/or controls must be located behind rear wheels on rear-engine dragsters.

We race under FIA sanctioning body [international]
I've seen the "clerk of the course" walk along the dummy grid and flip off all the isolator switches [then disqualify the cars with their engines still running]

On my last race car [an Aussie Falcon Touring Car] we used a Ford Starter Solenoid mounted on the battery box as an Automatic Isolator for the H/D cable to the starter motor.
This main cable was dead as a Dodo except when cranking so no fuse was needed [the solenoid at the starter motor was bridged]
The main feed and charge wire were of a lighter gauge and easily fused.

All we needed was an extended wire from the ignition switch to the starter solenoid.

Here is a simple Schematic [I hope it's readable]

upload_2022-2-8_9-59-45.png

upload_2022-2-8_9-58-53.png[/QUOTE][/QUOTE]
 

Midlife Crises

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The simplest remedy is to add a H/D diode in this wire
You can use a double pole, single throw switch as the master cut-off if a solenoid is not wanted. I just don’t like the “hot at all times” wire.
 

scramblr

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You leave the charge wire on the Battery side of the Isolator Switch! This prevents the Alt charge backfeeding to the ignition and keeping the Engine running.

But as you observed it remains hot all the time!
The simplest remedy is to add a H/D diode in this wire [close to the battery as possible]
This makes the wire dead as a dodo when trying to discharge the battery, and hot when the Alt is charging the battery.

@ scramblr doesn't need an Isolator switch on the ground strap [a waste of time as the main isolator switch achieves the same result]

If you're wanting a cheap source of Battery Cables ,look at your local "U" Pull for BMW E36's [they have trunk mounted batteries]


Appreciate the input. The switch on the ground strap will be accessible by the battery box and only for convenience when working on the car vs reaching down to the wheel well and flipping the pos switch. I know...first world problems.

Can you elaborate on the H/D diode that we can splice into the alt wire? Maybe a link to one so I can see what you're talking about? I can follow instructions and pictures very well...but I just don't have the experience to know what some of these parts are. Thank you!!
 

kerrynzl

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You can use a double pole, single throw switch as the master cut-off if a solenoid is not wanted. I just don’t like the “hot at all times” wire.

With the Battery in the trunk you have a live H/D cable from the + post to the starter solenoid [and maybe an isolator switch in between]
With a Ford starter solenoid this wire is dead [after the solenoid] except when cranking the engine over.
I witnessed a serious accident when a touring car was "T-boned" in the passenger door and literally cut this live wire in half and dead shorted against the chassis/body.
This caused a Major "red hot" melt-down because the isolator switch was at the base of the windshield
Luckily for the unconscious driver, it didn't touch the steel braided fuel lines running down the sill line inside. [they run the fuel lines inside because it protects them from debris on the track /mechanical explosions

From that incident and after ,all the NZV8 touring cars adopted the Ford Starter Solenoid method near the battery .
And the main power feed for the rest of the harness used a lighter gage wire [fused] and a simple SPST switch at the base of the windshield. This switch only needs to be 35a rated.
 
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kerrynzl

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Appreciate the input. The switch on the ground strap will be accessible by the battery box and only for convenience when working on the car vs reaching down to the wheel well and flipping the pos switch. I know...first world problems.

Can you elaborate on the H/D diode that we can splice into the alt wire? Maybe a link to one so I can see what you're talking about? I can follow instructions and pictures very well...but I just don't have the experience to know what some of these parts are. Thank you!!

I'll need to dig into my resources here.
I was given a couple of "Stud Blocking Diodes" from an electrical engineer friend that played around with H/D electric motors.[they are not cheap at approx $10-$12 vs about 10c each]
It worked really well [especially on my old B/B Corvette race car where shorting out tools was an occupational hazzard]

Another method is to use a DPST switch to switch off both the Alt wire and Ignition circuit at the same time.
But ^^^ I am not fond of disconnecting the Alt Charge Wire while the Alt is still charging [throwing the switch with the engine running]
Having the Alt Charge Wire connected to the battery acts like a buffer when the engine is still winding down to a halt.

Is your car a track car or street car.
Mustangs are easy to wire in a Isolator switch [the old conventional method]
1:Mount the switch in the Aerial Hole on the passenger side fender. next to where the old battery was mounted
2:Crimp an eye to the old battery + cable and bolt it "downstream" on this Isolator switch
3:Crimp an eye to the old main power feed and also bolt it "downstream" on this Isolator switch
4:Make up a new cable to go to the battery box in the rear and connect this "Upstream" side of the Isolator switch
5:Connect the alternator charge wire [that normally goes to battery] to the "Upstream" side of the Isolator switch.
You could probably locate and splice this wire into the main fusebox and fusible link.


If you use the marine style battery isolator switch on the fender /base of the windshield [below]
upload_2022-2-8_14-20-7.png

Clock/Rotate the switch in a position so the Flag/Key is Trailing in the on position and East/West in the off position.
Approx 35 years ago I learnt a "pants shitting lesson" when me and a friend were practicing in a Rally car on back country gravel roads at night.[I was the passenger]
We came sliding around a corner [reasonably fast] when suddenly every thing went "black" and we rolled down a bank.
What happened was some branches on the roadside brushed the isolator switch and flipped it into off position.
Everything went dead. Ever since then I've clocked/mounted the switch so this cannot happen.
 

Midlife Crises

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Moroso has a very nice double pole signal throw switch made exactly for the OP’s drawing. It comes with a mounting bracket and rod to exit the rear of the vehicle. Meets NHRA rules!
 

scramblr

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I'll need to dig into my resources here.

Is your car a track car or street car.

Primarily a street car...weekend driven some track. So not going to get too deep into the electronics. I think the above will work for the intended purpose. Appreciate the input. And scary roll over when the power went out. Crazy!

Moroso has a very nice double pole signal throw switch made exactly for the OP’s drawing. It comes with a mounting bracket and rod to exit the rear of the vehicle. Meets NHRA rules!

The Flaming River Big switch is the same thing with the handle. Just working out where to mount it or more so, what I need to drill a hole through.
 

kerrynzl

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Primarily a street car...weekend driven some track. So not going to get too deep into the electronics. I think the above will work for the intended purpose. Appreciate the input.

The Flaming River Big switch is the same thing with the handle. Just working out where to mount it or more so, what I need to drill a hole through.

The passenger side fender is already drilled for an aerial from factory.
AND it is right next to the existing battery box.
Just drill a few holes in the inner fender and use some grommets to run the cable through.

That way you can use the Battery Isolator switch as a joiner with the existing main feed [that goes to the starter motor]
Because it is easily accessible on the Fender, you will not need an isolator on the ground strap in the trunk.

I use the very same Battery Isolator switch [above] on my Trailers and all my race cars.[they are waterproof]
My present race car is a factory FR500C and Multimatic installed the very same switch [on the roll-cage "A" pillar]

Underneath the Rubber "hat" on the switch it looks like this [below]
upload_2022-2-9_17-16-7.png

There is a groove where the key drops in.
I drilled a tiny hole where I marked the arrow [then installed a self tapping screw], I then carefully shortened the screw with a file so it would NOT touch the shaft of the key.

This screw goes above the little dowel in the master key [in the groove] and prevents the key from being lost or coming out
upload_2022-2-9_17-24-47.png

Re-assemble with some electrical grease and slip the "hat" over the screw/ outer body.
In 40+ years involved in racing I have never lost or misplaced a master key [even when towing to the track]
I even retro' fitted this on my FR500C
 

kerrynzl

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Just working out where to mount it or more so, what I need to drill a hole through.

Should you decide to mount the Battery Isolator switch in the rear close to the battery [which I'm not against this idea, just the FIA requires this at the base of the windshield]
You will need to make up a whole new main feed from the starter to the Isolator switch.

Another Cheat method is to use a "battery distribution block" [jump start block] from a BMW E36 ['90-'00 3 series] as a cable Joiner

These are on the Right Front inner fender.
upload_2022-2-9_17-56-16.png

BMW use these to take a power Feed from the trunk mounted battery.
Then distribute to the starter motor ,and the main harness.

You will have a ton of room with your battery box removed [and these look really neat and professional]

Here is what it looks like with the side cover removed [1: is Battery , 2: Starter, 3: Harness Feed, and circled is to Jump start under the plastic cover]

upload_2022-2-9_18-4-45.png
upload_2022-2-9_18-17-47.png

Last time I got one I paid $20 including all the wiring H/D cable back to the battery.

Also use star washers under all your ground straps
 
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scramblr

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The passenger side fender is already drilled for an aerial from factory.
AND it is right next to the existing battery box.
Just drill a few holes in the inner fender and use some grommets to run the cable through.

I like it...thanks for the advice. Of course I no longer have the antenna (Arial) on my fender (filled in) but this still gives me something to work with.

Sent from my SM-G986U using Tapatalk
 

scramblr

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O.K., starting this project. Figured out it's simple to upgrade the starter/BEC cables, so those are going to 1/0.

Clarification on the two grounds that came from the battery to the chassis and the engine block. Now the battery will be grounded to the chassis in the trunk. Will running a ground from the block to the chassis be sufficient? Do I need to add another ground in the bay? Thx...

upload_2022-2-12_13-10-0.png
 

AHaze

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Just working out where to mount it or more so, what I need to drill a hole through.

A trunk mounted battery is on my to do list but I really don't want a switch or pull rod visible on the back of the car since it's 99% street driven. I figure I'll do this either by mounting the switch directly to the bumper cover behind the licence plate and building a raised plate bracket to clear it or mounting a push / pull switch in the spare tire well and making a detachable pull rod that comes out through a hole behind the plate.
 

bambam 06

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Should you decide to mount the Battery Isolator switch in the rear close to the battery [which I'm not against this idea, just the FIA requires this at the base of the windshield]
You will need to make up a whole new main feed from the starter to the Isolator switch.

Another Cheat method is to use a "battery distribution block" [jump start block] from a BMW E36 ['90-'00 3 series] as a cable Joiner

These are on the Right Front inner fender.
View attachment 81551

BMW use these to take a power Feed from the trunk mounted battery.
Then distribute to the starter motor ,and the main harness.

You will have a ton of room with your battery box removed [and these look really neat and professional]

Here is what it looks like with the side cover removed [1: is Battery , 2: Starter, 3: Harness Feed, and circled is to Jump start under the plastic cover]

View attachment 81552
View attachment 81553

Last time I got one I paid $20 including all the wiring H/D cable back to the battery.

Also use star washers under all your ground straps
Should you decide to mount the Battery Isolator switch in the rear close to the battery [which I'm not against this idea, just the FIA requires this at the base of the windshield]
You will need to make up a whole new main feed from the starter to the Isolator switch.

Another Cheat method is to use a "battery distribution block" [jump start block] from a BMW E36 ['90-'00 3 series] as a cable Joiner

These are on the Right Front inner fender.
View attachment 81551

BMW use these to take a power Feed from the trunk mounted battery.
Then distribute to the starter motor ,and the main harness.

You will have a ton of room with your battery box removed [and these look really neat and professional]

Here is what it looks like with the side cover removed [1: is Battery , 2: Starter, 3: Harness Feed, and circled is to Jump start under the plastic cover]

View attachment 81552
View attachment 81553

Last time I got one I paid $20 including all the wiring H/D cable back to the battery.

Also use star washers under all your ground straps
 

bambam 06

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I just bought a new one on Ebay, i am planning on only using #1, Batt and#2/#3 for harness. Do i seal the rest, as i will not use them.
 

kerrynzl

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I just bought a new one on Ebay, i am planning on only using #1, Batt and#2/#3 for harness. Do i seal the rest, as i will not use them.

??????
Are you referring to the BMW battery distribution block, And a trunk mounted battery?
Are you going to use a Battery isolator cut off switch? or not?

If you look at the BMW battery distribution block , diagonally opposite #2 is a 4th post.[below]
This is where BMW hook up the Charge Wire from the Alternator [so they only need one cable back to the battery]
upload_2022-2-15_12-33-41.png

If you're using a battery cut-off/isolator switch [for motorsport], do not connect the charge wire there.
You must run a separate charge wire back to the battery + [or the battery side of the cut-off/isolator switch.
This way the Alt charge only feeds to the battery and cannot feedback and keep the engine running when the battery cut-off/isolator is switched off [when the engine is running]

If you're not doing motorsport , you could hook up the Alt charge wire to post #4 and just use a battery cut-off/isolator switch anywhere in the main battery cable [or ground cable]
This is only make the whole electrical system dead for storage or working on a vehicle..... It will not kill a running engine [a motorsport requirement]





View attachment 81629
 

kerrynzl

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To anybody with the Battery Cut-Off/Isolator switch mounting dilemma.[especially with motorsports in a street car]

Here is where the factory mounted the Battery Cut-Off/Isolator switch on the FR500C.
[on the A-Pillar of the roll cage] so it can be reached by both the driver or the safety crew outside [there is the decal on the outside]

upload_2022-2-15_12-56-58.png

On a nice street car you could get more creative without a roll cage and use an A-Pillar gauge pod and mount the Battery Cut-Off/Isolator switch there.
upload_2022-2-15_13-11-59.png

And race with the side windows down.
You can buy universal single pods, but with the dual pod you could mount a decent warning light or shift light in the lower pod. [or a starter button]
 

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