Relocate the battery to the trunk

[Galvagni]

I am considering relocating the battery to the trunk in my 63 R1. Are there any reason I should not? Since the trunk is essentially open to the passenger compartment are battery vapors an issue?

My main reason to relocate the battery is the convenience of knowing that I can replace the battery anywhere and at any time. Freeing up room in the engine bay would be nice also.

I have this vision of being at a small-town diner and being greeted with a dead battery.

 

[mfg]

3 hours ago, Galvagni said:

I am considering relocating the battery to the trunk in my 63 R1. Are there any reason I should not? Since the trunk is essentially open to the passenger compartment are battery vapors an issue?

My main reason to relocate the battery is the convenience of knowing that I can replace the battery anywhere and at any time. Freeing up room in the engine bay would be nice also.

I have this vision of being at a small-town diner and being greeted with a dead battery.

 

If authenticity isn't a concern for you, relocating your Avanti's battery to the trunk area is (in my humble opinion) one of the biggest improvements which can be easily made to a Studebaker Avanti!

You're removing that heavy 3EE battery from over the left front wheel and placing that weight into the trunk, where it's actually needed to help 'balance' an already nose heavy car.

And no doubt you would install a more common battery in the trunk, such as a 'Group 24', a battery which there is a large variety to choose from, also, from what I've experienced , common Group 24 auto batteries will outlast the 3EE type every time!

When I converted my '63 R2 Avanti to a trunk mounted battery (many years ago) I used a plastic 'boat type' battery box to house it in...Then I ran a positive battery cable of appropriate length up to the starter solenoid on the left fender apron....I encased the cable in rubber hose for its protection, then ran a negative cable through a small hole drilled in the trunk floor beside the battery, to a grounding bolt on rear frame rail...I also added an additional ground strap between one of the bellhousing bolts and a frame crossmember...and, of course, the original engine ground strap is still in place.

Battery vapors could potentially be an issue when battery is being charged, so on my Avanti I drilled a hole at the top of the boat battery box and ran a length of 1" plastic hose from that hole through the same hole the negative cable passes through in the trunk floor, using sealer around both the negative cable and the vent hose...I tapered the end of the vent hose where it hangs down beneath the trunk floor so vapors can be drawn out as car is moving forward... (think road draft tube)

And one more thing....removing that heavy 3EE battery from the fiberglass 'pocket' it sits in up front sure takes a lot of stress off of that old 1963 fiberglass!!....GO FOR IT!!....Ed

 

 

 

 

[Leo B]

Interesting 😊 Has anybody used just 3EE covers for show or autheticity look and active battery in the trunk?

Edited March 6, 2022 by Leo B

[mfg]

26 minutes ago, Leo B said:

Interesting 😊 Has anybody used just 3EE covers for show or autheticity look and active battery in the trunk?

That's a great question Leo!...it's one thing to relocate battery to the trunk, however, doing that does leave an ugly open spot under the hood!

What I did to solve that situation on my '63 was take the 3EE battery and carefully slice its case open on a line about 1" down from the top...then, carefully separating the top from the rest of battery, I 'gutted' the battery acid & the lead from the case... (messy job, and eye & skin protection should be worn)...Then I flushed out the case with clean water and simply refitted the 3EE top to its lower case..(before I closed it up, I rigged two false battery pos & neg posts, which I had saved.

Closing up the battery case and re-installing it, with the stock hold downs and a couple of 'false ' battery cables running down the inside of the battery and tied off near the driver's side horn...The old 3EE appears to the world to be looking good & functioning!

I've entered my Avanti into many shows, and NO ONE has ever spotted the 'hoax'!!!

Best part about it...The empty 3EE case weighs about 2lbs....if that!!!

[Galvagni]

I like the idea of a tube to vent off any gas. Most kits I see include #2-gauge wire that seems insufficient. I'm considering #1-gauge or larger welder wire. Your thoughts?

I'm also thinking of relocating the solenoid to the trunk. That way the heavy cable will only feed the starter. I'll then have to run a wire from the relocated solenoid to the fuse box. Am I missing anything?

Edited March 6, 2022 by Galvagni

[mfg]

37 minutes ago, Galvagni said:

I like the idea of a tube to vent off any gas. Most kits I see include #2-gauge wire that seems insufficient. I'm considering #1-gauge or larger welder wire. Your thoughts?

I'm also thinking of relocating the solenoid to the trunk. That way the heavy cable will only feed the starter. I'll then have to run a wire from the relocated solenoid to the fuse box. Am I missing anything?

I believe #2 gauge will do the job nicely....I don't think I'd relocate the solenoid, as it's 'comfortable' where it is, and running the positive wire forward is really easy...As mentioned, I encased the positive wire in an equal length of rubber hose to protect it from over the road damage and/or chafing.

I made this conversion on my '63 Avanti over eight years ago, and unbelievably I'm still using the same Group 24 battery!....Best of luck with this worthy project....Ed

[Dwight FitzSimons]

Concerning the battery vapors:  I have a 2003 Olds Aurora which has its battery under the rear seat cushion.  It came with an AC Delco "sealed" battery (no caps).  Those batteries have a small vent on each end of the top.  The Olds has a vent tube going from the vents to under the car (like a road-draft tube).  So, GM thought it was a good idea to vent the battery out of the cabin.

However, I'm not sure that a #2 gauge wire is heavy enough for that length of battery cable.  Remember that the voltage drop is proportional to the length of the wire.

--Dwight

Edited March 6, 2022 by Dwight FitzSimons
additional info

[mfg]

2 hours ago, Dwight FitzSimons said:

 The Olds has a vent tube going from the vents to under the car (like a road-draft tube).  So, GM thought it was a good idea to vent the battery out of the cabin.

However, I'm not sure that a #2 gauge wire is heavy enough for that length of battery cable.  Remember that the voltage drop is proportional to the length of the wire.

--Dwight

Wow!...do you think GM owes me a royalty on that 'road draft tube' idea Dwight??

#2 gauge wire is more than adequate for this......I'd only use #1 gauge if Avantis had 6 volt electrical systems!!

[mfg]

Galvagni.........I noticed your '63 Avanti 's serial # is 63R1370....My own '63 Avanti's serial # is 63R1379....Our cars are kissing cousins!!

[Dwight FitzSimons]

What gauge wire have others used for relocating the battery to the trunk?  The stock battery cable is #4, which is only one size smaller than #2.  Remember that current in the complete circuit has to travel ~15' (each way) rather than ~2'.  The voltage drop through the copper wire, plus the voltage drop through the steel frame WILL drop the battery's voltage some.  I don't know how much off the top of my head, however, but I wouldn't wing it.  With some numbers one could calculate the voltage drops.

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/imgele/resis3.gif --Dwight Edited March 7, 2022 by Dwight FitzSimons

[fastforward]

8 hours ago, Dwight FitzSimons said:

What gauge wire have others used for relocating the battery to the trunk?  The stock battery cable is #4, which is only one size smaller than #2.  Remember that current in the complete circuit has to travel ~15' (each way) rather than ~2'.  The voltage drop through the copper wire, plus the voltage drop through the steel frame WILL drop the battery's voltage some.  I don't know how much off the top of my head, however, but I wouldn't wing it.  With some numbers one could calculate the voltage drops.

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/imgele/resis3.gif --Dwight

I don't have an Avanti, unfortunately, but have a 51 Bus Coupe that has the battery located in the trunk. Originally had #2 cable but cranking was slow. Upgraded to 0/2 cable, maybe a bit of overkill but certainly solved the problem, length was around 12 feet to the cutoff switch on the firewall. 

[Desert Driver]

Moved my battery to the trunk shortly after buying the car in 2017. Living in the desert, the road temperature, outside air, and engine heat shorten the lives of most batteries. Mine is still going strong and is quite content living in the carpeted trunk!

[Avanti83]

The interweb says a starter can draw about 150 amps and as high as 200. My battery is trunk mounted but I don't recall wire size but memory thinks 1/0.

I have a 200 amp fuse in line at the battery.

Here's some thoughts on amperage, length and gauge. I'll let you folks figure out what's the proper size.

https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html

This is the setup in my 74. The ground runs from the battery to the rear body mount then along the frame to a contact point by the engine and then grounded directly to the engine. Power runs through the disconnect, along the frame to the starter and feeds the main fusebox from there.

The additional fuse and ground points in the trunk allow me to provide 12 volts without running a mass of wires along the frame. The inline fuse is 200 amps.

Yup!! I'm a belt and suspenders guy.

 

[mfg]

5 hours ago, Avanti83 said:

The interweb says a starter can draw about 150 amps and as high as 200. My battery is trunk mounted but I don't recall wire size but memory thinks 1/0.

I have a 200 amp fuse in line at the battery.

Here's some thoughts on amperage, length and gauge. I'll let you folks figure out what's the proper size.

https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html

This is the setup in my 74. The ground runs from the battery to the rear body mount then along the frame to a contact point by the engine and then grounded directly to the engine. Power runs through the disconnect, along the frame to the starter and feeds the main fusebox from there.

The additional fuse and ground points in the trunk allow me to provide 12 volts without running a mass of wires along the frame. The inline fuse is 200 amps.

Yup!! I'm a belt and suspenders guy.

 

Wow!...looks a bit complicated!.....Have you made provisions to vent hydrogen gas fumes from trunk area when battery is being charged?

[Galvagni]

16 hours ago, Avanti83 said:

This is the setup in my 74. The ground runs from the battery to the rear body mount then along the frame to a contact point by the engine and then grounded directly to the engine. Power runs through the disconnect, along the frame to the starter and feeds the main fusebox from there.

The additional fuse and ground points in the trunk allow me to provide 12 volts without running a mass of wires along the frame. The inline fuse is 200 amps.

Thanks for the ideas and photo. Did you maintain the solenoid in the engine compartment? I'm considering relocating the solenoid from the left fender apron to the truck also. 

Since I replaced the original wire harness with a Painless performance "universal fit" harness all I would have to do is feed power to the fuse box and run a wire from the ignition switch back to the solenoid. The advantage that I see is that the heavy power line would only need to feed the starter. The one advantage of the Painless harness is that it has more circuit than I would ever use so I don't see a need for a power source in the engine compartment.

Your thoughts

[Avanti83]

1 hour ago, Galvagni said:

Thanks for the ideas and photo. Did you maintain the solenoid in the engine compartment? I'm considering relocating the solenoid from the left fender apron to the truck also. 

Since I replaced the original wire harness with a Painless performance "universal fit" harness all I would have to do is feed power to the fuse box and run a wire from the ignition switch back to the solenoid. The advantage that I see is that the heavy power line would only need to feed the starter. The one advantage of the Painless harness is that it has more circuit than I would ever use so I don't see a need for a power source in the engine compartment.

Your thoughts

This is a 74 so the solenoid is on the starter. Leaving the solenoid up front would allow a shorter wire to power the fuse box if it's located under the dash but in the trunk would look cleaner. I'd probably go for the trunk mount for starters (pun intended). I'd be sure to enclose and vent the battery also.

I used a generic 21 circuit GM style harness from Speedway Motors to rewire mine. 

[Avanti83]

12 hours ago, mfg said:

Wow!...looks a bit complicated!.....Have you made provisions to vent hydrogen gas fumes from trunk area when battery is being charged?

Quick answer, yes, when I finish the trunk this year. Possibly complicated but it allows me power to some accessories when the main power cutout is open and protects the car from a short in the power wire running to the front along the frame.

[mfg]

7 hours ago, Avanti83 said:

Quick answer, yes, when I finish the trunk this year. Possibly complicated but it allows me power to some accessories when the main power cutout is open and protects the car from a short in the power wire running to the front along the frame.

Dodge/Plymouth super/stocks of the early sixties used trunk mounted bus batteries (open, not boxed in ) which featured unique caps having individual vent tubing coming out of the top of each cap, ending outside the car.

Edited March 8, 2022 by mfg

[mfg]

I also converted my '83 Avanti 'everyday driver' to a trunk mounted battery at about the same time as my '63 (as described above)... After 6 or 7 years of day in-day out service.....no problems whatsoever.....and I'm still using the same Auto Zone 'Gold Top' Group 24 battery!

[brad]

Modern AGM sealed batteries don't need to be vented. Also, there are "remote" key fob operated battery disconnects. You leave a small wire to operate the relay, but the rest of the car is disconnected from power. On one car, I made a side panel in the trunk compartment, and also carpeted it in matching carpet. I put the battery behind it, and it was clean, and hidden from view. Run a good ground from the starter to the frame, and a heavy positive cable to the solenoid. 

[mfg]

7 hours ago, brad said:

Modern AGM sealed batteries don't need to be vented. Also, there are "remote" key fob operated battery disconnects. You leave a small wire to operate the relay, but the rest of the car is disconnected from power. On one car, I made a side panel in the trunk compartment, and also carpeted it in matching carpet. I put the battery behind it, and it was clean, and hidden from view. Run a good ground from the starter to the frame, and a heavy positive cable to the solenoid. 

Sounds nice!

[landriopa]

I have just moved the battery to the trunk after heat killing two batteries.  This is my second battery change.  Two years ago I got rid of the 3EE for a NAPA Legend 7551.  It is narrow enough to fit in the 3EE space even with power steering.  It lasted twice as long as the 3EE and had 20% more CCA.