Battery Recommendation?

[svassh]

My new to me build in process does not have a battery. Its fully packed with electronics, A/C, Power Windows, Door Poppers, Electric PS, Electric Water Pump, Electric Parking Brake, Fan, Fuel Pump etc. Car will be pretty demanding electrically. I know some have gone with the smaller Lithium batteries. Car is a Gen 1 with 347 Ford, EFI and its not clear to me where the PO had the battery mounted but it was go kart at one point. The whole wiring harness was pulled so pretty much a blank canvas for wiring.

Any advice on battery type, size, location is appreciated.

[egchewy79]

many of us use the Breeze front battery tray set up which takes a 51 group battery.
there's lots of debate on AGM battery vs good ol' lead acid batteries, but you'll pay maybe twice as much for an AGM one.

[Bob Cowan]

Lithium batteries are nice if you're concerned about weight. But they do have their limitations and concerns.

I prefer AGM because they are much more resistant to vibration.

The weight balance on an FFR is pretty close to 50/50, with a slight bias to the rear. With that thought in mind, I think the best place is over the passenger foot box. It's near the center of the car, and off sets the weight of the driver. You can see it here:

[Alan_C]

I have used the Odyssey battery in two builds. The first battery lasted 7 years. They are in the $275 price range, so double that of a lead-acid battery but twice the life.
I would stay away from the Optima batteries as many have reported the newer batteries do not have the life of those bought 10 years ago or so. The company has changed hands a few times and the quality is just not the same, plus they charge a premium price for the brand name.

[progmgr1]

I also have an Odyssey battery - PC1200, which I understand was the OEM battery for 2015 Mustangs. Currently price is ~$310 and stocked at Auto Zone. It is an AGM battery and I can testify that AGM batteries don't leak even when the case is cracked open and the terminals punched into the cells. (Long, sad story - don't ask...)

The stock battery location for the Hot Rod is centered under the gas tank. There is an access panel behind the seats, but it can be a pain to change out the battery in that location. Many have relocated the battery to the trunk using a variety of boxes or trays available from all the usual sources. There is no room to mount the battery in the Hot Rod engine compartment - that's a roadster / coupe option only. Also, many have added remote terminals to make jump starting or mounting a trickle charger easier.

Keith HR #894

[RoadRacer]

I bought a secondhand battery from the local parts store - they all have a shelf of them, with 12 month guarantee - just for go-kart stage, and 2 years and 12,000 miles it's still showing healthy and cranks like a train. I secured mine on the p/s upper shelf of the trunk so I don't have to worry about it under the car (and this was a big battery anyway).

[Tampa33Build]

Mounted battery in trunk as shown. Three 10x32 screws and the cover comes off for easy access.
20210717_133301783_iOS.jpg trunk battery cover.jpg

[Brastic]

My Odyssey is coming up on 7 years old now and never has been an issue. I have become a huge fan of the AGM batteries for these cars. What gets me is that I have the Odyssey 925 (seems like just a bit better motorcycle battery) and it has no problem starting my 302 or Coyote engines, even after sitting for months.

[svassh]

Thanks all, I think I'll try the Odyssey 925 and figure out a good spot in the trunk. Looks the PO had planned to mount it there as battery cables run to that spot.

[JimLev]

Odyssey 925 on mine too.
See post 227 and 229 for how I mounted my battery.
https://thefactoryfiveforum.com/show...-s-Build/page6

[Brave Salmon]

Thanks all, I think I'll try the Odyssey 925 and figure out a good spot in the trunk. Looks the PO had planned to mount it there as battery cables run to that spot.

I you're going to put it into the trunk, consider a larger Odyssey battery than the 925. I think the 925 was originally spec only because it was the bare minimum battery to fit on the tray above the drive shaft. Unless you are running a simple setup with very little need for battery power, you will want more capacity. odyssey makes many larger models that will fit the trunk and give you enough capacity to support your configuration.

[MonstaS4]

Keep in mind that all loads other than the starter motor should have no impact on battery sizing - unless you want to run lots of accessories without the car running. Once the car is running, the alternator provides power to all devices.

[Brastic]

I did not pick out the 925 Battery. It came in both of my cars. I was thinking about upgrading, but after 7+ years, never found the need.

[Brave Salmon]

Keep in mind that all loads other than the starter motor should have no impact on battery sizing - unless you want to run lots of accessories without the car running. Once the car is running, the alternator provides power to all devices.

MonstaS4, you are correct that the alternator should handle all the accessories when the engine is running. I guess my point was that the 925 has enough capacity to start the engine just fine but I question it's reserve capacity should you need to crank it over more than once after it's hot or you've been running the radio or if the cooling fan has been configured to run after engine shutdown or if he has the electric water pump run after engine shut down. That 925 just does not have enough poop to handle all these loads more than for a short time. I have the 1200 in my 347 and there where times when i was a little bit concerned about it's ability to restart the engine after filling up the tank with engine off for just that long. Nothing more embarrassing than a pretty car that won't start in front of all the lookie lous at the local gas'n go.

[MonstaS4]

Completely agree with you Brave. Reserve capacity along with CCA should be considered when selecting a battery. My comment was more aimed at the OP as his first post mentioned all sorts of accessories will be connected.

[Just 1 More]

Mounted battery in trunk as shown. Three 10x32 screws and the cover comes off for easy access.
20210717_133301783_iOS.jpg trunk battery cover.jpg

Old post but, I would like to know more about how you supported the battery from the backside. I'm looking at doing this exact same mod but would like more info before I start butchering

[JimLev]

I’ve been carrying one of those small Li-ion jump packs just for peace of mind. Haven’t had to use it.

[Tampa33Build]

I have the IRS, has a different trunk than non-IRS. I started with a battery box located in top trunk area and realized trunk space is a premium and relocated to current location. Ended up cutting up the battery box to make it fit the current location.
Cover bolts in with six 1/4x20 pan head SS bolts (3 on top & 3 on bottom) to rivnuts located in the trunk sheet metal. These are covered with the carpet flap on the cover. Cover is easily removable to access the battery.

Best pictures I could get, not a lot of room and retractable license plate bracket makes for less area to take pictures.
Trunk View:
20230325_163852991_iOS.jpg 20230325_163902083_iOS.jpg
Bottom View: Pan bolted to frame with side brackets
20230325_163556743_iOS.jpg 20230325_163609268_iOS.jpg 20230325_163637384_iOS.jpg
Cover:
20230325_163914280_iOS.jpg20230325_163922540_iOS.jpg

[progmgr1]

I love the carpeted cover! I may have to steal that idea, modified to suit my design.

Just an FYI: the Dynamat and similar products used for noise reduction don't need to cover the entire surface, only the middle 75%-80%. The area near any sharp bends is mechanically stiffened and work hardened, so the sheet metal doesn't move much there and the Dynamat doesn't have much effect. It works best in the middle of a panel where there is a lot of flex.

Keith HR #894

[Jeff33Ford]

I too have the IRS and used the space above the rear end to drop the battery in.
IMG_2226.jpg
See more pics here