[truongski]

Does anyone know what the minimum CCA rating required for the V6? Is it important?

What I want to do is to install a small start battery to the drivers side where the ABS module would go and then a normal wet cell deep cycle battery (N70) to the stock location to run the accessories.

The start battery I want to use is an Odyssey PC680MJT, as this fits the location perfectly. The only downside is that the CCA rating is 220. However, it does mention that for the first 5 seconds, this battery will produce a CCA of 680 and after 10 seconds, a CCA of 595.

To be honest, I don't think I will be cranking the starter motor for more that 5 seconds continuously let alone 10 seconds, so in theory it should be ok.

Do you think this would work? Let me know your thoughts.

Also, how would I re-route cables to the drivers side? New cable from the starter & fuse box or extend the existing?

FYI, the owners manual recommends a 55D23L size battery. The Century Battery version has a CCA of 470.

[dhula]

The PC680 appears to be very similar in size to a motorbike battery and has what looks to be similar performance numbers.

(see here for specs and here on page 20 for what all those acronyms mean and on page 6 for more performance data of the battery

While the pulse current would most likely be up to the task it will certainly rely on the engine starting up straight away each and every time and then needing to be driven around to replace what is spent. Short trips could very well see the battery not wanting to start the car after a couple of school pickup trips.

I wouldn't do it as I'd want to have that little bit of reserve available for those "not quite spot on" times when you need it.

[wolf_rt]

I don't have an actual figure for the v6... I would think 250-300amps would be a safe bet, i would be very surprised if it drew over 250.

I'm no expert on dual battery set ups, but:
How are you going to wire up this set-up? without some sort of solenoid or something, the batteries will balance through the charge wire/s coming from the alternator.
Also if there is only one solenoid in the system, then as soon as you re-engage the solenoid the depleted 'acc' battery will start drawing on the start battery very hard through the thin charge wire.
While the car is running, how will you stop high draw 'accessories' ie. a winch. from pulling current through the 'charge wire'?

I would get a new cable made to go to the starter motor, the wire to the 'fuse box' could be joined.

Remember if you hook your 'start' battery to the fuse box (as original) then if someone leaves the car door open, your start battery will go flat, and how will you start the car?

I have seen some really poor dual battery set ups, that cause far more problems than they solve, be careful and do your research...

btw... some of the expensive 'dual battery - charge controller' things are hopeless... once again, do your research.

edit: i agree with dhula... the battery would do the job, but have little elbow room

[royce]

I did exactly this with mine, moved the crank battery from passenger side to drivers side and put the aux in the passenger side, however I used the standard battery and made a tray (ns40 type battery) and it just fit in the available space.

The wiring is the easiest part of it all, get 2 battery cables made up, from positive battery terminal to the positive post on the starter and from negative battery terminal to an earth point on the block.

Now take the standard positive battery terminal and chop it up so you are left with a sort of ring terminal that you can bolt under a stud.

Now get a dual battery isolator (some kind of voltage sensing thing like redarc, BEP whatever) and attach your made up ring terminal to the start battery side of the isolator.

Then make up another fat cable to go from the isolator aux terminal to your aux battery, knock up an earth for the aux battery and you are done, one working dual battery setup.

If you are worried about the little battery not starting, carry some jumper leads

[TheOtherLeft]

royce wrote:

I did exactly this with mine, moved the crank battery from passenger side to drivers side and put the aux in the passenger side, however I used the standard battery and made a tray (ns40 type battery) and it just fit in the available space.

The wiring is the easiest part of it all, get 2 battery cables made up, from positive battery terminal to the positive post on the starter and from negative battery terminal to an earth point on the block.

Now take the standard positive battery terminal and chop it up so you are left with a sort of ring terminal that you can bolt under a stud.

Now get a dual battery isolator (some kind of voltage sensing thing like redarc, BEP whatever) and attach your made up ring terminal to the start battery side of the isolator.

Then make up another fat cable to go from the isolator aux terminal to your aux battery, knock up an earth for the aux battery and you are done, one working dual battery setup.

If you are worried about the little battery not starting, carry some jumper leads

How does the start battery get charged? On the start battery you've only connected the starter and the earth

[royce]

the factory leads that run over to the now battery isolator are still there

[Built4thrashing]

Check out my build for a better way of doing what you want. also Bohuler has a very similar setup to mine(i made it for him). We both have full size batteries and auto sensing isolators. and apart from a bad earth on my isolator have not had any problems.

I now have a N70ZZL (650CCA) in the factory position as a start battery and a Optima D34 (750CCA) as the accessory batery. Winch is connected to start battery. Fridge, driving/work lights and Air compressor are off the accessory battery.

My setup is on page 8. viewtopic.php?f=4&t=17450&start=140

To get this setup to work you need to relocate the radiator overflow to opposite side and the washer bottle
to inside the passenger guard. This works for models without abs or airbags.




Bohulers setup is here. viewtopic.php?f=4&t=28534 Well it should be if he would update his build......

[truongski]

royce wrote:

I did exactly this with mine, moved the crank battery from passenger side to drivers side and put the aux in the passenger side, however I used the standard battery and made a tray (ns40 type battery) and it just fit in the available space.

The wiring is the easiest part of it all, get 2 battery cables made up, from positive battery terminal to the positive post on the starter and from negative battery terminal to an earth point on the block.

Now take the standard positive battery terminal and chop it up so you are left with a sort of ring terminal that you can bolt under a stud.

Now get a dual battery isolator (some kind of voltage sensing thing like redarc, BEP whatever) and attach your made up ring terminal to the start battery side of the isolator.

Then make up another fat cable to go from the isolator aux terminal to your aux battery, knock up an earth for the aux battery and you are done, one working dual battery setup.

If you are worried about the little battery not starting, carry some jumper leads

This is how I want to do it. I have found another battery that will work better than the Odyssey battery. The Braille B2317 seems to have a bit more power than the Odyssey.

I will be using the Redarc as an isolator. It has a function where if your main battery is flat, you can start off the aux battery.

B4T, I have read your build thread many times trying to get ideas. I like where you have placed your 2nd battery, but for a dual battery system, I don't want to move the radiator overflow bottle.

Royce, do you see any point of extend the existing positive cable to the new battery instead of modifying the terminal and attaching to the isolator?

[Built4thrashing]

Over flow bottle fits nicely on oposite side of rad. I just drilled out the spot welds and rebent the base of the bracket and it bolted to the airbox mount. Still sits at the same height and works as it should.

As i see it the way i did it is about the only way to fit a full size battery under the bonnet.

Plus it allows you to fit an aircompressor next to the brake booster.

[royce]

dont see the need to do that, easier to terminate a new cable on a stud designed for it rather than trying to join heavy cables together mid loom

[dhula]

One thing I like to consider when making up a duel battery system is the ease of getting spares if something goes wrong.
Having exotic batteries could be a potential downfall of an otherwise perfect setup.

[truongski]

Built4thrashing wrote:

Over flow bottle fits nicely on oposite side of rad. I just drilled out the spot welds and rebent the base of the bracket and it bolted to the airbox mount. Still sits at the same height and works as it should.

As i see it the way i did it is about the only way to fit a full size battery under the bonnet.

Plus it allows you to fit an aircompressor next to the brake booster.

Just had another squizz under the bonnet, do you find your Optima too close to the exhaust manifold? How did you bolt the battery tray down?

I have mounted my air compressor behind LHS head light.

[truongski]

dhula wrote:

One thing I like to consider when making up a duel battery system is the ease of getting spares if something goes wrong.
Having exotic batteries could be a potential downfall of an otherwise perfect setup.

If I do choose to go with this battery, the only downfall I would see is the potential for a flat battery, as there is less reserve capacity. This problem would be solved by either Redarc's smart assist facility or a jump start from RACQ.