1973 911T Battery

[jagular911]

Need to purchase Batterys for 73 911T.

Can someone advise the recommended battery, both size and cca?

Also-do I need to purchase 2 batteries?

Thanks

Jon

[Zeke]

No, you do not need to buy the original dual set up. One Optima on its side will work fine. Since most Optimas are about the same dimension, just get one that fits and has terminals that suit your installation. A red top with 800 amps is plenty.

Just to be sure, there are other battery choices. I used a smaller gel battery, but it was not going to get me out of trouble on a difficult start.

[69911e]

I have run 1 stock interstate for years. I disconnected the cable to the second battery.

[HarryD]

For a Long Nose, you have several choises:

A pair of conventional Lead Acid Interstate U911's which fit exactly intot he battery boxes;

Replace your twin batteries with a single Optima on its side. You will need to fabricate a hold down and fool with your leads. Not hard if you have any mechanical competence. I used a flat braided ground lead and placed the negative (ground) end inside the battery box. I bought my red top at Costco and I think it is a Model 75/25 or a 34/78;

A pair of Miata Batteries; or

A pair of DF75 Sonnensheins gel cells (exact fit as well).

There are also Oddessy batteries as well.

[Boydskyking]

I just bought a 1973 911 targa which has the batteries missing(both sides) and was wonder what do I buy for the car. I would like to keep it as stock as possible. Do I buy two 6 volt or two 12 volt batteries .
Thanks

[jbell959]

You need two 12V batteries. If you want to keep it close to stock and have batteries that fit in the boxes you don't have many choices. I haven't looked in a while, but I know Interstate still makes a model#911 battery.

Car and Truck Automotive Batteries - Buy a Vehicle Battery for Cars or Trucks | Interstate Batteries - Interstate - Default 6m Free - 300 CCA

[wayner]

If you want stock twin battery setup I believe it will take the same batteries as a chevette did except you will need two if you want to remain stock, but one will be enough (at least it was for the chevette).

[E Sully]

I use 2 WestCo Miata AGM batteries. Needs no venting, slightly smaller than original.

[gamin]

I have the Miata AGM batteries in the 70. Takes bit of fitting. No venting is a big plus.

[jdbunda]

I took a page from silverc4s' book, and put in a $99 Duracell AGM battery from Batteries Plus (nominally, I think it is for ATVs). Cranks great. You could put another one on the other side if you wanted a dual setup. Small enough that you need to engineer a hold-down solution, sealed, and light weight (well, compared to other batteries). I have an Optima in my Carrera, but that has a much bigger battery box.

Here is my post on this from last summer:

Yet another early car battery option - Duracell?

[RSTarga]

Or these Bosch for Miata, I used 2, much cheaper than the Sonnencheins.

[Quickstep192]

I got two PC925 Odyssey batteries and built a case to make them the same size as the original battery. It cranks like a mutha.......


My Odyssey battery Odyssey

[Jamesrlong]

Originally Posted by Boydskyking

I just bought a 1973 911 targa which has the batteries missing(both sides) and was wonder what do I buy for the car. I would like to keep it as stock as possible. Do I buy two 6 volt or two 12 volt batteries .
Thanks

If you go to auto zone, advance, Napa or what not, there computers will say 6 volt battery's. But 911s are 12 volt systems.

[grizzfan]

The PO was running an unsupported single battery on the driver's side of my '73 and I decided to revert to the original 2 battery solution, one on each side, as the wiring was still there for the passenger side. I bought the Interstate model U911 and they fit perfectly. The original hold downs were garbage and I found some repro ones that I ordered through eBay from Germany, stainless steel, but pretty darned spendy. They also worked great, although we had to fabricate a threaded nut into the tub on one side.

Now having said all that I wish I had gone with the Mazda Miata batteries as they are AGM. My batteries are not vented but I have lined the boxes with that acid absorbing material that our sponsor sells. There's just room enough to do it and I'll have to pull a battery from time to time to be sure there are no leaks.

One note. If you ever decide to put in an Elephant Racing late Carrera Oil Cooling system in the passenger fender with their supplied fan, you will have to remove the passenger battery because the fan cuts into that battery box. There are other solutions, a smaller fan for instance, or a front mounted RS-style coiling system.

Best,

Tom

[dicklague]

I have used Miata batteries for years.