early 911 replacement batteries

billwagnon · 03-02-2010, 04:54 PM

My 1973 911 batteries are no longer holding a charge. They're at least 5 years old.

The ones I have are Interstate model U-911 300 CCA so I think they are 911 specific. Autozone said "dealer only".

I'm hoping to stay under $200 for the pair, something I can just slip in without mods.

What is the best replacement battery?

HarryD · 03-02-2010, 05:53 PM

I went with a single Optima on it's side on the driver side. I had to disconnect the crossover cable from the second battery, make a hold down strap (from some plumbers pipe hanger material, a D ring (to make a loop to attach the strap to the hook inside the box) and two pop rivets and get a longer ground strap. The other end of the strap was anchored to the exisitng battery hold down bolt point.

Looks like this installed:

Total cost? About $150.

Quickstep192 · Quickstep192's Garage

My search a few years ago revelaed the same thing - "dealer only". I ended up replacing mine with Absorbed Glass Mat Miata batteries. I had to pad the battery boxes a little bit and to ensure that the positive terminals didn't contact the top of the battery box. BUT, they hold a charge all winter long while the car is in storage and even if they do discharge, it doesn't kill them.

WRGREENER · WRGREENER's Garage

I AM USING A SINGLE "SERIES 70" SIDE POST BATTERY. THEY FIT QUITE WELL INTO THE DRIVERS SIDE PROTRUDES PAST THE FRONT OF BOX ABOUT 1.5" POSITIVE POST LEFT/NEG RIGHT
I BOUGHT MINE AT A "BatteriesPlus" STORE FOR ~ $100. I ALSO ADDED A "PRIORITY START" (A DRAIN-DOWN PROTECTOR) @ $40 TO CONTROL BATTERY LIFE AND THOSE LITTLE SNEAKY ELECTRON LIFE SUCKING ITEMS HIDING IN THE DASH. I HAVE HAD THREE "SERIES 70" BATTERIES IN THIS CAR TWO (2) SLID RIGHT IN AND I HAD TO TRIM THE BULGES ON THE BOTTOM (PROB USED TO SECURE) OFF. EASY TRIM SINCE THEY ARE PLASTIC AND ANCILLARY EXTRUSIONS.

HarryD · 08:16 AM

Quote:

Originally Posted by billwagnon

My 1973 911 batteries are no longer holding a charge. They're at least 5 years old.

The ones I have are Interstate model U-911 300 CCA so I think they are 911 specific. Autozone said "dealer only".

I'm hoping to stay under $200 for the pair, something I can just slip in without mods.

What is the best replacement battery?

Autozone may just be lazy.

If you want to go with the Interstates, find another Interstate dealer in your area. I know if I want them, there are several local shops that would be most happy to take my money for a pair. I would be very surprised to find out that an independent battery store would turn down a sale.

billwagnon · 03-03-2010, 05:44 AM

Here is what Batteries Plus shows - I will have to check them out.

* SLIU1RT Rayovac Maximum Battery 1972 to 1973 911 Porsche Car and Truck

* 1972 to 1973 911 Porsche Car and Truck Rayovac Maximum 12V Battery SLIU1RT. Match your original battery in fit, but gain more power with a Rayovac Maximum battery. Testing, installation and recycling services available.

*Information on this product is for reference only. Please contact a Store near you for specific availability and pricing details.
* Item number: SLIU1RT
* Weight: 25.0000 lbs
* Voltage: 12V
* CCA: 320
* Primary Applications: Mazda Miata
* Replaces: 8AMU1R, A2305410001, GROUP 54, SLIMU1R-PRM, SLIMU1R5

detroiter · 03-03-2010, 06:07 AM

The last time I bought a pair from the dealer, they were about $103 each.

It's nice that the battery have a big PORSCHE sticker, but it's on the wrong side (not visible when you open the hood). I peeled off the sticker and put it on the other side. Unfortunately, the end product did not look good - it did look just like it was peeled off and re-attached :<

HarryD · 03-03-2010, 08:18 AM

Quote:

Originally Posted by billwagnon

Here is what Batteries Plus shows - I will have to check them out.

* SLIU1RT Rayovac Maximum Battery 1972 to 1973 911 Porsche Car and Truck

* 1972 to 1973 911 Porsche Car and Truck Rayovac Maximum 12V Battery SLIU1RT. Match your original battery in fit, but gain more power with a Rayovac Maximum battery. Testing, installation and recycling services available.

*Information on this product is for reference only. Please contact a Store near you for specific availability and pricing details.
* Item number: SLIU1RT
* Weight: 25.0000 lbs
* Voltage: 12V
* CCA: 320
* Primary Applications: Mazda Miata
* Replaces: 8AMU1R, A2305410001, GROUP 54, SLIMU1R-PRM, SLIMU1R5

Looks like a Miata Battery. They should work. Check the post oreintation. also, are these conventional lead acid or gel cells?

304065 · 03-03-2010, 08:27 AM

Call Fort Lauderdale Battery and ask if they have the A512/40A.

A 500

Gary De · 03-03-2010, 08:38 AM

I just purchased (2) batteries for my 1972 911T from a battery supply company in Florida. They are a German sealed battery made for early 911's. They fit perfect. The brand name was Sonnchin. Not sure about the spelling. They advertise in Pano. They gave me a 10% discount for
being a PCA member. They ran a little over 100.00$ each. If you need more info let me know.

WRGREENER · WRGREENER's Garage

BatteriesPlus... "ultra" SLI70 18/65 PRO RATED WARRANTY @ $89.99 FITS THE BOX PERFECTLY (WITH SHAVING THE PLASTIC RIDGE AT BOTTOM SIDES) I USE ONLY ONE ON THE FUSED SIDE. POLLS ARE ON CORRECT SIDE FOR HOOK-UP. YOU COULD USE TWO IF YOU WANTED TO KEEP THE BALANCED SYSTEM.

Axeman · 03-03-2010, 08:44 AM

Quote:

Originally Posted by 304065

Call Fort Lauderdale Battery and ask if they have the A512/40A.

A 500

+1 on the Sonnenschein batteries, I got those for my 1972 and love them!

berettafan · 03-03-2010, 09:03 AM

Got the Sonnys in mine as well. No hassles with too tall posts, etc etc. and good service from the dealer in Fla.

BBShriver · 05:30 AM

I'm thinking my car may have a dead battery as well. Shop had it for over 9 months doing a variety of work. When I went to pick it up at the shop it was dead, though they said they'd had it on a charger. Jumped it, I drove home put it on the charger for about 6 hrs, took it off before going to bed. This morning it was totally dead, didn't even make noise when I turned the key. I put the charger back on before coming to work, so it will have 9 hrs or so by the time I get home, but since it died overnight I'm not real optimistic.

My car though was "converted" to a single battery on the driver's side... It seems like for weight balance it could be advantageous to put the 2nd battery in as well as giving me a bit more security (longer time to run-down). What would I need to do that?

Is there an Optima that I could use? Pelican has a part OPT-825000 that comes up in the 65-73 911, can anyone confirm this?

I also want some sort of battery kill switch in case it's some sort of new problem in the wiring.

HarryD · 03-19-2010, 06:12 AM

You can do dual Optimas but they do not fit neatly into the battery boxes. A single Optma is more than adequate for our cars. If you want, there are several other options as well (Sonnenschein , Oddessy, "Miata Batteries", etc).

BBShriver · 03-19-2010, 06:33 AM

What would be the best bet for a local (autozone) find?

HarryD · 03-19-2010, 07:03 AM

Quote:

Originally Posted by BBShriver

What would be the best bet for a local (autozone) find?

I would doubt they would have anything that would fit neatly into our boxes as the battery is not a "standard" size.

IMHO, unless your friends refer to you as Schumi, I doubt there is much real world impact in going to a single battery (Grady and some others may feel otherwise).

These threads sumarize your choices:

71 Porsche 911T 2.2 Battery Question

Dual Battery Questions - Help!!

There are lots more as well.

BBShriver · 03-19-2010, 07:22 AM

Autozone wouldn't carry the "miata" battery?

I'm thinking of looking for the smallest Optima I can find locally, and adding some sort of tie-down. Then maybe someday go back to 2 batteries if I decide to. Right now I just want to be driving the darn thing, as I haven't really driven it for a year and a half, and by the time I get it back from the shop the battery is dead!

kenikh · 03-19-2010, 08:03 AM

Lauderdale battery has been out of stock on the A500s for months and are unsure if Sonnenschein is making more. Bummer. They are also quite a bit more than $200/pr, but are well worth the price. I love mine.

brads911sc · brads911sc's Garage

$150?

My local autozone charges $170 for just the battery (group 34r).

Quote:

Originally Posted by HarryD

I went with a single Optima on it's side on the driver side. I had to disconnect the crossover cable from the second battery, make a hold down strap (from some plumbers pipe hanger material, a D ring (to make a loop to attach the strap to the hook inside the box) and two pop rivets and get a longer ground strap. The other end of the strap was anchored to the exisitng battery hold down bolt point.

Looks like this installed:

Total cost? About $150.