Customs Odyssey PC680 battery (for the F1) – what's your experience?

I don't know why it won't turn over a flathead. I have one and it easily spins over and cranks my 348 Chevy with roughly a 9:1 combustion ratio. It also easily cranks my 302 Ford engine. Don't know what else to say. I have it under the seat in my 34 pickup so its not too far from the starter.
Will a conventional battery turn it over?
You check the starter?

 

Odyssey batteries, love 'em or hate 'em....

That's really too small for automotive use. With only 170 cold cranking amps, it's really designed for a motorcycle, or at least a 4 cylinder motor. A typical automotive V8 starter will draw about 250 amps, you really want to see CCA somewhere in the 400 amp range to guarantee starting under all conditions.

 

If every thing is good I think it should work, although I use 925's. Gary

 

Go with a metal -case PC925.... Not cheap, but well worth the money... IMHO

 

Where are you're grounds and what size cables

 

Why not an Optima mounted on it's side...800 CCA!

 

I have one in the Pinto powered 29 RPU, works fine
Also one I the 347 Stroker SBF in the other 29 RPU for 10 years now, also works fine.

I've also used a bunch of them on Harley's and they are MUCH harder on the battery than that flathead! The long stroke and odd firing order kills batteries and starters, yet the Odyssey's live

 

I would try using the battery from your daily driver and see how it starts with that - it will tell you whether you have a problem with the battery or something else in the truck.

 

Not big enough battery cables. Gary

 

PC680 cranks over my stock 305 with ease in my 35, on the way out now and won't hold charge as well as it did when new. On second one now with over 5yrs+ service. Also under front seat as well. No accessories apart from radio.

 

When I built my 23 modified, I had no room for a battery anywhere. I ran into the PC 680, but had my doubts it would start the 350 sbc, so I called the company. I got the President on the phone and he said he is starting a blown big block Chevy with one in his car, so I should have no problem at all with mine.

I bought it and for the 5 years I had the car it never failed to crank it over, and the battery was clear in the rear of the car. It could sit for months and still fire it right up. At 7 x 7 x 3 inches, it is very small and very good, at the same time.

Don

 

I have one in my 32 pickup going on three years now, it lays on it's side, under the passenger side seat. There isn't a lot of reserve capacity, but it has started my mild sbc 355 every time I've asked it to so far. Honestly, I've quite worrying about it. Bought it on eBay for about $100 shipped.

 

I had read good things about them and some other reports where they were not strong enough.
I decided to go instead with a battery like the Braille 3121.
Still a small battery, but with much more cranking and reserve capacity.
I found a Deka AGM battery identical to the Braille in size and everything else for much less money than the Braille.
http://www.braillebattery.com/index.php/braille/product_batteries/b3121
http://www.federalbatteries.com.au/ETX30LA/
I believe the Deka is made in the same factory as the Braille (East Penn) , but they will not tell you that.
(The Deka can be fitted with the same bolt on automotive style posts as the Braille)

 

I have no experience with the PC 680 in a car but have had good luck with them in airplanes. I had one last over 5 years cranking a 10 to 1 compression Lycoming, even in cold weather it did well as long as I preheated the engine. I then used the same battery on a motorcycle for a year and it now sits on my workbench with a couple of leads for testing 12 volt circuits. I would buy another one without reservation.

 

With marginal size, invest in fat 6 volt cables...you can get stock for those at Brillman. And test to see there's no voltage drop through solenoid. Get something with some reserve! Body mods mean you can't get your handcrank in there!

 

I love em. I use one in my airplane which has a 10:1 IO-360 Lycoming. Then both hot rods with slightly less compression. Typically I'll keep one in the airplane for three years, three more in a car, and then it goes to my backup sump pump. 104$ from Amazon shipped. You can't beat that. The sump pump job is near nine years old!

 

Bringing this back up.
Kevin, I was wondering if you tried anything more to get that PC680 working?
This thread is one of the very few threads on the subject that never got resolved. You might try connecting your negative battery terminal directly to the engine preferably close to the starter.
Any update?

 

Love mine.
It's about five or six years old now. it sat on the shelf for at least two maybe three years and in the car about the same.
It hasn't been driven a heck of a lot in the last couple either. I've never had to charge it and starts every time.
I did use heavier cables and I have an ignition cutout switch for hot starts because I have a lot of compression and locked out timing
Although it's not needed it still rolls it over just fine

 

I have one in my roadster w/Merc Flathead located in the rumble seat with American Auto Wire cables & kill switch - works great every time.

 

Odyssey PC680 batteries took several Hilton A coupes with varying engines from VA to Austin and back with zero issues.

 

Been using the pc680 for a few years....... wouldnt think of anything else..... starts my big inch 9.35 comp ratio blown Olds everytime
no problem on 10.5 to 1 hemi
10to1 on the Nailhead
9.45 on the Blown YBlock

 

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I have a pc680 in my roadster and it has no problem firing up my highish compression 327 even after sitting for a while. I think it's great and the small size can't be beat. The only drawback is that the battery can wear down quick if you're in a situation where you have to keep cranking. I had a hot start issue for a while that I resolved, but that was my experience.

 

That's good news...thanks for the update.
Like you, I was seduced by the "small, powerful, win-win" aspect of these batteries. I shoe-horned one in on on my current build. The under floor tray is a "bolt in " so I can remove it if future problems occur.
I haven't fired it off yet and was curious. Quoting you: "I would love it to work".

 

I'm using a Braille 3121 with good success. But you need to get yourself a charger designed to work on a Gell Cell battery to keep it charged when not in use. All these Gell type batteries will die for good on you if you don't keep them charged with a proper charger.
The Battery Tender Plus is about the most for the money I have found I wound up buying another battery when I was just out od warranty before I learned that. Bought a Battery Tender Plus and use it when I know it's gonna be awhile before I drive it again. No further trouble.