Power upgrade Group 31 install and Optima content

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LandCruiserPhil

LandCruiserPhil

Peter Pan Syndrome
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Mar 10, 2004
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Location
Graham County, Arizona
I have been running dual Optima Blue tops wire together for the last ~7 years. I know there is lot of hate on Optima's but I have abused my Optima's and they have performed excellent and there time in service speaks loudly. Only one of my blue top died the other is still going but because my batteries are wired together and never separate both need to be replaced. One would think after such great results I would just replace ther Optima's and hope for another 7 years of stellar performance but nooooo.

I ended up going with a Duracell Ultra AGM group 31 in the factory location and replacing the Blue Top Optima AGM in the rear. The combination wired together in parallel gives my ~170AH of power or ~85AH at 50%. I went with the Duracell Group 31 for more available power, because it was the same cost as the Optima Blue with 2 times the available power and a slightly longer warranty.

Fitting the group 31 in the factory location with all my wiring was ultra tight. In order to fit I needed to trim the bottom drivers side back corner of the battery box. Not a big deal and feel I will see no issues down the road. It would not be possible to use the factory style hold down with this group 31 but not a problem because I never liked the factory hold down and changed to a front to back hold down years back. Front to back has always worked great me and the battery super secure. The fit is so tight I had to change the winded nut to a bolt on the negative side because it was hitting the hood.

Because I was just replacing the rear Blue top with another it would be quick and easy. Yes and no the rear battery is super tight and surrounded by lots of metal creating a situation were you need to be very careful not to ground out and cause big problems. By taking my time it worked out and its in and like the front it will never more a mm.

In the end I now have 1800A cranking power and 160AH of available power for around $450 not bad if the new set up last 7 years like the last.

Some pics of the action

IMG_9540[1].webp


There is a Blue Top in there somewhere

IMG_9545[1].webp


I made the side gate removable and Im glad I did

IMG_9546[1].webp
IMG_9548[1].webp

Changed terminal wing nut on negative side to SS nut for needed clearance.

IMG_9553[1].webp
 
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Neat! How wide is that group 31? I googled the dimensions of the flooded Duracell 31 and it was going to intrude on the radiator by like 4 inches. Yours looks like it fits perfectly so I am confused.
 
mct75 said:
Neat! How wide is that group 31? I googled the dimensions of the flooded Duracell 31 and it was going to intrude on the radiator by like 4 inches. Yours looks like it fits perfectly so I am confused.
Click to expand...

The Duracell Ultra is an AGM not flooded to match the Optima. Width per factory spec is 12.93" and it is spot on.
 
Where did you get that battery holdown and how is it attached at the bottom?
 
Peluo said:
Where did you get that battery holdown and how is it attached at the bottom?
Click to expand...

Its been too long to remember but Im sure it was from a big box store something I saw on the shelf. Standard hooks similar to the factory set up.
 
Whats that short cable going through the battery box? From the positive side
 
I had to replace main battery recently after about 4 years. The aux battery is still good and hold charge well. I believe they were the out going stocks from Autozone where a buddy got them for.
 
I just installed a Group 31 (pure lead plates) Marine Grade Battery in my FZJ80.
ARC Battery made in Sausalito CA. 100% pure lead plates. Solid Posts.
950 CCA, 190 Reserve. Deep cycle marine battery, $180 out the door, with Group 31 core exchange.
These have a reputation of lasting 10 plus years
I had to cut a notch out of the plastic/fiberglass factory tray to make it fit. ( the bump on the drivers side).
The stock cables won't reach the solid post location.
I have been on the forums and searching for options. Looking at the Screw on Battery disconnects to get some extension and I wanted a battery disconnect anyway. Just a simple one, not the fancy Flaming River one. (not yet)

I really like the way you did your set up with all new cables and lugs mounted to a threaded post.
Looks like you went through a lot of work to get that all wired in. You have a winch?
 
So when it comes to the AGM, does starting vs deep cycle make all that much of a difference? I am looking at doing this mod (with the price matched super start variant) but also noticed that Duracell sells a dual purpose agm version intended for starting purposes with higher cranking at 925 vs the 800 on the one referenced above but lower reserve (190) and ah (100). New to the whole agm realm so forgive my lack of knowledge.

SLI31AGM - Duracell Ultra Platinum AGM BCI Group 31 Dual Purpose (Starting/Cycling) Heavy Duty Battery at Batteries Plus Bulbs
 
97 greenmonster said:
I’m putting same battery in my truck. Phil could you take a pick of the bolt threw the battery box set up that you use for factory fusible links. Thanks
Click to expand...

Nothing special just a JIS bolt - power feed - washer - battery box - washer - fuseible links and a JIS nut. Power feed on the battery side and the links on the other. Simple and rock solid set up.

img_9540-1-jpg.1476318
 
One thing to keep in mind when using the marine terminal connections is that the positive terminal is not covered. If you get in a rollover or a accident, and the terminal makes contact with the hood such as if the hood buckles or the front clip buckles and pushes the battery up into the hood, it could start a fire. A terminal cover gives just a little extra protection.
 
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