Best battery

[Bully]

So looked through the threads and didn't really see anything definitive.
My battery is old and needs replacing, what says the collective here as to the best choice?

[Rawknees'Turbo]

I've been using an Odyssey PC-680 for about six years or so. It is tiny (weighs about 15 lbs), but despite that, cranks the low static compression, 3.3L with ease in temps down to about 30 degrees (never gets below that where I live - and only that cold on rare occasions), and has a surprising amount of reserve power; I've had "no start/hard start" situations a few times, and the battery doesn't seem to run out of cranking power more than a regular sized battery (obviously, not as much power storage as a full sized battery, but plenty for extend cranking situations).

It's a "power sports" battery and does not have automotive-style posts on it, but post conversion kits are available and inexpensive.

https://www.amazon.com/Odyssey-PC680-Battery/dp/B0002ILK6I/ref=sr_1_1?s=automotive&ie=UTF8&qid=1475468123&sr=1-1&keywords=odyssey+pc680

The only real negative is that it will run down quicker if a power drain is on it when the engine is not running - so that might be a concern. I've made a habit of leaving a trickle charger on it when parked at home - a good idea for any battery in terms of extending its service life.

It's completely sealed, so no risk of leakage, and can be mounted on it's side if you wanted to (mine is mounted upright, using a custom holder that I made).

[pkabush]

Odessy's are excellent batterys. I run two in my diesel truck and I had one like Ronnie's in my 930 for years. It finally died and I replaced it with a $40 ebay battery that's the same size. I didn't get a chance to use it very long before my car went under the knife but I've read reports in the tech section of guys getting over five years out of them.

[Rawknees'Turbo]

Bully, when you get a chance, ask Mr. 70'sBush (pkabush) what he does with a car battery, some wire leads, and a can of whipped creme!

[slow&rusty]

I agree with Rawknees and also using the PC680 (have been since 2006!)

[basicporsche]

I have used the Interstate Optima for my 88 911 for years mostly due to the fitment and it always worked well. Have the Porsche battery from Motul in my GT4 but will probably swap it in 3 years or so to another gel one.

[scottrx7tt]

I am running a Turbostart battery. Price was around the $150 range. an old friend from high school. works for them. i believe they are the same as XS power.
Turbo Start S12V925: 12 Volt Street/ Race Battery 7" L x 6-1/2" W x 5" H | JEGS

[flightlead404]

Originally Posted by Rawknees'Turbo

I've been using an Odyssey PC-680 for about six years or so. It is tiny (weighs about 15 lbs), but despite that, cranks the low static compression, 3.3L with ease in temps down to about 30 degrees (never gets below that where I live - and only that cold on rare occasions), and has a surprising amount of reserve power; I've had "no start/hard start" situations a few times, and the battery doesn't seem to run out of cranking power more than a regular sized battery (obviously, not as much power storage as a full sized battery, but plenty for extend cranking situations).

It's a "power sports" battery and does not have automotive-style posts on it, but post conversion kits are available and inexpensive.

https://www.amazon.com/Odyssey-PC680-Battery/dp/B0002ILK6I/ref=sr_1_1?s=automotive&ie=UTF8&qid=1475468123&sr=1-1&keywords=odyssey+pc680

The only real negative is that it will run down quicker if a power drain is on it when the engine is not running - so that might be a concern. I've made a habit of leaving a trickle charger on it when parked at home - a good idea for any battery in terms of extending its service life.

It's completely sealed, so no risk of leakage, and can be mounted on it's side if you wanted to (mine is mounted upright, using a custom holder that I made).

The Odyssey is a is a great battery, I use one in my plane and have for years. But why would you reduce weight in the front of a 930?

[smurfbus]

I bought two tiny lithium bike batteries HJTX20H 450cca size and I'm planning to use the other one on my 930 next summer. I used the other one on my daily 2.7 liter audi v6 the whole summer without any problems and no extra charging so I think it will do fine on my 930 too and I have li charger if it does not get charged enough with the old alternator I have. I did buy the IIRC 160A alternator Jfairman had linked before so that should give it plenty of juice if need be.

These batterys only weight 1.6 kilos ~4 lb so wheelies get even closer : ) when I install it at the smuglers box.

[Rawknees'Turbo]

Originally Posted by flightlead404

The Odyssey is a is a great battery, I use one in my plane and have for years. But why would you reduce weight in the front of a 930?

I didn't notice any difference in how the car handles after replacing the 65lb battery with the 15 pounder.

I did have to lower the left front corner about 1/2 inch - it went up that much with the lighter battery.

As to "why" - I like the ease of working with the small , light battery, the space it frees up for storage of tools, small spares, etc. and the idea of the fookin' huge, original sized battery used for an engine that can be easily turned over by hand (with the spark plugs still in), is intolerably dumb to me. Plus, I no longer have the catalytic converter or big, heavy muffler my car came with, and the nose of my car is lowered quite a bit, so I bet the factory weight balance wasn't too affected (it sucked anyway, however).

[smurfbus]

And we can always install lead bars at the front bumper or trunk just like porsche did to master the balance.

[Rawknees'Turbo]

^^^

Ha ha - yep, have to take extreme measures to overcome a chassis design that makes one think "what the efffff were they thinking?!?!" in terms of weight distribution!

[pkabush]

Originally Posted by Rawknees'Turbo

Bully, when you get a chance, ask Mr. 70'sBush (pkabush) what he does with a car battery, some wire leads, and a can of whipped creme!

Keep my public life out of this bub.

[pkabush]

Originally Posted by flightlead404

The Odyssey is a is a great battery, I use one in my plane and have for years. But why would you reduce weight in the front of a 930?

Clearly, it's not the best place to loose weight but it's still weight loss. There's absolutly no reason to run a 40# batterry in these cars, but hey, I ditched my. Spare, A/C, windshield and headlight tanks, pumps etc, etc.
The OP asked "what is the best battery" My vote would be Odessy but, I think that some of the lesser name brands are probobly equelly as good for allot less scratch.

[flightlead404]

Originally Posted by pkabush

Clearly, it's not the best place to loose weight but it's still weight loss. There's absolutly no reason to run a 40# batterry in these cars, but hey, I ditched my. Spare, A/C, windshield and headlight tanks, pumps etc, etc.
The OP asked "what is the best battery" My vote would be Odessy but, I think that some of the lesser name brands are probobly equelly as good for allot less scratch.

As I always respond when a client asks what is "best". First, define "best"

[Bully]

As to " best battery "
I don't drive below freezing, so cold cranking amps not a big deal.
I always leave the car plugged into a battery maintainer when it's parked.
I like ease of working, so less crowded anything is a good thing.
Certainly seems that for the price and weight advantage that the PC680 is best so far.

Hey Raw Knees,. I get the battery and leads thing, but whipped cream..?

[Rawknees'Turbo]

^^^

I'll leave a detailed explanation of the whipped cream component to 70'sBush (he might be feeling shy, however), butt lets just say that the dude buys the stuff by the 50 gallon drum - weekly!!!

[1979-930]

PC680 is a great battery. I have one in my other toy that is 11.25:1 compression ratio V8 and spins the starter just fine. But its 15lbs weight is old skool. The new trend is lithium coming in at 5lbs and fits in the glove box.

You can get the pc680 at Batteries Plus. They keep them in stock around here. The cool mounts are an on-line only thing.
I got my battery and mount here before I knew Batteries Plus had them. Odyssey Batteries

[flightlead404]

Resurrecting an old thread but:

My boat anchor battery is on its last legs and I'm considering the Odyssey 680 or 925.

I have a few questions for those that use them

1) Are these two still the best choices for reliability, cranking performance, and fitment?
2) Is there a particular model of 925 or simply use the base 925 with the automotive post screw in terminals?
3) Any different in fitment between the Rennline and Odyssey mount/hold downs
4) I was considering the Rennline mount with the extra tab for a battery switch as I thought I could use this as a mount for an eventual inertia switch for the fuel pumps should I eventually go full EFI
5) It looks like the batteries might both leave enough room to mount a small aux fuse panel for some additional gear I have installed (front oil cooler fan, upgraded headlights etc) does anyone have experience with this?

[jeff91C2T]

Nowadays there are alternatives, a LiFePO4 w/ a proper BMS makes for a good packaging improvement.