Battery Upgrade, Odyssey PC924 and Aluminum mount Options

[914e]

Even in the 70's an alternator should be able put out enough current to run the engine , lights, and fans at idle. If you are seeing big voltage drops at idle, you have either added some loads the car was not designed for, or you have an alternator problem. A battery should not be discharging when the car is running. Unfortunately the 914 has no headroom for electrical accessories, of course in the late sixties there was not many electrical accessories.
When the car is off and battery fully charged it should be at 12.6 volts. If it is below that either the battery is bad the charging system is not working properly. If the battery is down a few tenths of a volt below 12.6 you have lost a large amount of the current capabilities of the battery. The battery when the car is running should be acting as a buffer. With the car running you should see 13.6 to 14 volts on a test voltmeter, I would not trust the gauge.
According to the service manual the regulator is set to 14 volts. 13.7 to 14.2 is typical for lead acid 12 volt systems.

In cars voltage is usually a symptom in a battery and charging system problem not a cause. The problem most of the time is current related. A clamp on DC amp-meter can take out most of the guesswork.

[campbellcj]

I've had really good success with the PC680. I disconnect it when the car is sitting which is most of the time, and it holds a charge fine. Per @914e above it's really just for starting the engine, then the alternator is running, and I have basically no accessories/radio/wipers to think about.

[rjames]

The battery mount looks plenty stout. How heavy is it?

[andrewck]

Parts arrived today for the install on my upgrade battery. Odyssey PC924 and Aluminum mount. Just need the terminal kit.

Will post a few pick of the install to follow....
https://www.ebay.com/itm/SR-Battery-Hold-Do...872.m2749.l2649 Streetray 925 mount

-Robert

which terminal adapters did you use?

[Mark Henry]

I also have a 680, it cranks fast, the H3 pilot fogs run all the time, I've been caught in the rain and driven at night same time, never an issue. I didn't disconnect it from the 914 over the winter, but I did charge every couple months.

Only time it wouldn't start was my brand new 3.0/6 first couple of starts, but have had no problems since the first couple of good runs on break in.

[BeemerSteve]

I use an 11 pound Braille battery in my 914.

I also use an 11 pound Braille in my Caterham 7 replica and my boat.

They work great.

I'm interested how you mounted it? I currently have the stock battery tray eliminated right now because that's how I bought the tub.

PM me if you like and if you have the time. Thanks!!

Steve

[rfinegan]

The weight of the mount is not much at all. It is all aluminum and is very strong. It can be lightened and reduced. Gut for the price point its attractive .

The Terminals I used were first the cheep lead once for charging. I did not post them as they looked bad and did not work well. Gut did start and drive while I was waiting for the terminal kit here:

https://www.amazon.com/gp/product/B004QCBM2...=UTF8&psc=1

Oddessy thermals SAE for about $24.00 Do not let the sticker shock get you now..This was a Great KIT and JUST WORKED as expected. On less thing to worry about

[rfinegan]

The weight of the mount is not much at all. It is all aluminum and is very strong. It can be lightened and reduced. But for the price point it's attractive .

The Terminals I used were first the cheep lead ones for charging. I did not post them as they looked bad and did not work well. But did start and drive while It while waiting for the terminal kit here:

https://www.amazon.com/gp/product/B004QCBM2...=UTF8&psc=1

Oddessy thermals SAE for about $24.00 Do not let the sticker shock get you now..This was a Great KIT and JUST WORKED as expected. On less thing to worry about.

[Ian Stott]

I have the small odyssey battery, run lights, wipers etc. no problem at all. Car can sit for long periods, battery still cranks the engine over just fine. Regarding the gauge comment about trusting it, I agree, mine reads around 10.5 to 11 with engine running, had mechanic check into it and he said ( I think you changed your voltage regulator unnecessarily, alternator is fine, your battery is fine, your gauge reads low ).

I had the alternator rebuilt while engine was out and replaced the voltage regulator with the more modern one, glad I did both, and yes it was the low readings on the gauge which prompted that.

Ian Stott
Moncton
Canada

[Mark Henry]

I have the small odyssey battery, run lights, wipers etc. no problem at all. Car can sit for long periods, battery still cranks the engine over just fine. Regarding the gauge comment about trusting it, I agree, mine reads around 10.5 to 11 with engine running, had mechanic check into it and he said ( I think you changed your voltage regulator unnecessarily, alternator is fine, your battery is fine, your gauge reads low ).

I had the alternator rebuilt while engine was out and replaced the voltage regulator with the more modern one, glad I did both, and yes it was the low readings on the gauge which prompted that.

Ian Stott
Moncton
Canada

Hi Ian, you have the 925 battery, I installed it and made your mount. That must be at least 5 years ago. The 680 I use is about half the size of your battery, about the same size as a lawn tractor battery.