trunk mounted battery.....

[61ragtop]

What is all involved in moving the battery to the trunk? Do you need to use a special battery or box?

Any info would be great as I am considering the move in my impala.....

[67 455 Bird ragtop]

A lot depends on how youplan to use your car. If you plan to enter any race each sanctioning body has it's own rules. But there are some common sense rules of thumb even for a street car. And a box is one. Do a search. The topic has been addressed severl times.

[61ragtop]

Thanks 67, it will be used as a street car 99% of the time.....

[spacepirate]

There are battery relocation kits on several sites. I even think DSE has one. That might be a good start.

[wmhjr]

https://www.pro-touring.com/showthread.php?61170-Trunk-mount-battery-Definitive-thread-on-safety-legality&highlight=Trunk+battery

[61ragtop]

https://www.pro-touring.com/showthread.php?61170-Trunk-mount-battery-Definitive-thread-on-safety-legality&highlight=Trunk+battery


Thanks! I was actually reading this as you posted

[61ragtop]

So from the reading I have done so far tell me if I got this right.......

-If mounted in the trunk it needs to be in a sealed box vented to the outside unless it is an Optima style battery

-It it best to run a remote solenoid so the power to the starter is not live (do i run the starting wire from the ignition to this solenoid instead of to the starter?)

-I need a ground from battery to body and body to chassis

What sort of vent do you use to vent the box?

Do the small wire terminals on the starter need to be energized for it to turn over?

[DRs 69]

So from the reading I have done so far tell me if I got this right.......

-If mounted in the trunk it needs to be in a sealed box vented to the outside unless it is an Optima style battery

-It it best to run a remote solenoid so the power to the starter is not live (do i run the starting wire from the ignition to this solenoid instead of to the starter?)

-I need a ground from battery to body and body to chassis

What sort of vent do you use to vent the box?

Do the small wire terminals on the starter need to be energized for it to turn over?

I had a solenoid on mine but it was for the main power switch (drag racing). If it makes you feel better to run a solenoid close to the battery to cut main power to the starter it shouldn't be a problem. However you will have to run wire for charging and other power needs like the fuse box and what ever else you need it for.

If possible I would ground the battery to the frame, also grounding the engine to the frame is always a good idea.

Yes the small stud on the starter has to be energized to run the starter.

Can't help much on the venting I used an Optima.

[wmhjr]

The solenoid is a smart idea, as it causes the 0/1 main power from the battery in the back of the car to the starter to only be energized when the starter is engaged. Otherwise, you have a very large high power line run along a big stretch of grounded material.

I also recommend running the ground from the battery both directly to the frame (possibly using a bulkhead stud) and to the body.

I also used an optima so can't recommend a box or vent.

[80 MONZTA]

I do like the idea of a solenoid to cut the main power going all the way to the starter. But what would you do for a charging post on a street car? Specifically if you needed a jump start.
I never thought much about moving the battery, but it would help a lot with weight distrubution on my little car. Also my car is a hatchback, so the battery would need to be sealed up in a vented box back there.

[67 455 Bird ragtop]

Go hear and read his tech info. Lots of good ideas here. And he's a really nice and knowledgeable guy. Always busy and sometimes hard to get hold of. And once you do he'll talk your ear off. Very pationate about car electrical ...

http://www.madelectrical.com/index.shtml

[H2Ogbodies]

i install charging/jumping lugs underhood on my relocates.

[wmhjr]

I have charging lugs in my trunk.

[DarkoNova]

Just want to say that the "live power wire" isn't as big a deal as people make it out to be. I had an 88 BMW that came with the battery in the trunk from the factory, and that's exactly what they did. The positive cable ran straight from the battery, through the door sill, through the firewall, up to a junction block on the firewall. The starter then had a short length of cable running straight to that junction block. If tested with a multimeter, you got 12 volts at the junction block, ignition off.

If an OEM does it, I wouldn't really worry about it.

The cable was also bolted down with little insulated clips, and even had corrugated tubing on it when it went around corners. Also had a nice thick grommet where it went through the firewall.

I actually took the entire setup out of my BMW and was going to use it in my Nova, but the cable is about a foot too short. I'm just going to order a longer cable and do the exact same thing on my car, though.

[wmhjr]

Bad comparison. My mb also has trunk mounted batteries, as did my bmws. Take a look at how much protection those cables get compared to most muscle cars with relocated batteries and you'll think twice. It's not essential, but remember that my mb and other cars also don't have a fire extinguisher. My gto does. Beyond that, there's a reason nhra and ihra both require master shutoff switches for cars with relocated batteries. If we were to simply emulate oem, there are a lot of things we would do differently.

[61ragtop]

Just want to say that the "live power wire" isn't as big a deal as people make it out to be. I had an 88 BMW that came with the battery in the trunk from the factory, and that's exactly what they did. The positive cable ran straight from the battery, through the door sill, through the firewall, up to a junction block on the firewall. The starter then had a short length of cable running straight to that junction block. If tested with a multimeter, you got 12 volts at the junction block, ignition off.

If an OEM does it, I wouldn't really worry about it.

The cable was also bolted down with little insulated clips, and even had corrugated tubing on it when it went around corners. Also had a nice thick grommet where it went through the firewall.

I actually took the entire setup out of my BMW and was going to use it in my Nova, but the cable is about a foot too short. I'm just going to order a longer cable and do the exact same thing on my car, though.

I guess it is just a matter of how many "just in case" precautions you want to take.

[DarkoNova]

I dunno, on my BMW there wasn't really any protection for the cable. I mean there was a cheap plastic cover that covered the battery, but other than that, nothing significant. I understand that racing sanctions require certain safety setups, but I'm just saying realistically, if secured properly, the cable won't move, nothing will rub through the insulation.

[wmhjr]

Take a look where the cable goes through panels. Hard to see unless you disassemble. Insulation does rub off. The only repair in had in my '99 m-roadster was the wire from the trunk lid into the trunk shorting out due to insulation rubbing off. Not a complaint. Great vehicle!

The question is - why in your right mind would you not add the extra safety when the cost of the solenoid and wire is just about nothing, and you have to run the wire anyway? Not to mention the little benefits? When working on some electrical in my car recently with the drivetrain out, I could test things with the battery connected and the switch on - even though the starter cable was just laying there with no worries.

To me, it's the little details and attention to detail that separate a well thought out build from the so-so.

Jmho. For about $15 I opted for the protection. I've spent that on a cigar. Rarely, but still.

[SicMonte]

Anyone have pics of there on/off switches to actuate the rear mounted battery?? I am doing this to my monte carlo but am havng a hard time visualizing where to put the switch or push/pull rod.

[DButler]

Yeah I ran a rear mounted battery in my car but not with a solenoid, maybe I should have after reading this. What do I need and does it just go in line of the positive cable or what?