The Best Battery for Your Air-Cooled Porsche

Battery Choices for Air-Cooled Porsches | Image: PakWheels.com

Tech Tuesday – Sooner or later it is time for a new battery for your Classic Porsche. I went to start my 1986 Porsche Carrera 3.2 the other day and it would not crank, even a little bit even though the battery is on a trickle charger. I also had to replace the battery in my 1973 Porsche 914 2.0 last year. In both cases the cars are connected with battery tenders to hold the charge between drives, but sooner or later the battery just gives out.

In the 914 I was running a battery that was at least five-years old because that was how long I had owned the car and had never changed the battery. The 914 battery is easily accessible so it was a quick trip to Advance Auto for a new Optima red top battery. The choice was pretty simple because I wanted a sealed battery to avoid acid corrosion issues in the dreaded hellhole battery tray of the Porsche 914. I went the Optima Red Top without much thought because their advertising over the years had conditioned me that they were the best.

The battery for my 1986 Carrera 3.2 is a different story. I have owned this car for over 22 years and since the car is an all-original, low mileage Porsche I didn’t want to put just any battery in it. The current battery in it was a Deka battery. When we stilled lived in Michigan I used an independent Porsche shop for repairs and this was their choice. I was curious when I last changed the battery and after going through the records I realized it was in 2008. Twelve years on a car battery! It shows the importance of using a battery tender to maintain battery life on Porsches driven intermittently.

Now to the choice of a battery; a sealed battery is an imperative, as I do not want to deal with battery acid. My first consideration was a Porsche OEM battery since I want this car to be as original as possible. A call to Porsche Asheville indicated that yes, they could get the OEM battery, but due to cost most owners opted for the Interstate battery. The Porsche OEM battery is approximately $350 versus an Interstate sealed battery at closer to $200.

I know the Interstate brand as a quality battery due to their years of motorsports sponsorship, but what did I really know about Interstate?

Well, to my surprise I found out that there are really only two, maybe three major manufacturers (depending on your definition of major) of batteries in the US. The two major manufacturers are Johnson Controls, Exide and to a lesser extent East Penn. Delphi is also often mentioned but the reality is that Johnson Controls owns Delphi so Johnson Controls really controls this manufacturer also.

Johnson Controls manufacturers some of the major brands including Die Hard, Interstate and Optima while Exide produces Exide, Champion, Autolite, Delco and Wal-Mart’s brand EverStart.

The reality is; is there really a big difference between a Interstate, an Optima or a Delco or any of the other brands? I decided no.

My choice: I am choosing the Interstate due to a good fit in the battery well of an ’86 Carrera that is a tight fit and a brand that stands behind their product.

For an in-depth description of the five different battery types I would recommend this web site.

To understand the value of an AGM Battery versus a Lead Acid Battery this web site has a good overview.

Tags: Battery for Classic Porsche, Air-Cooled Porsche Battery