Betis

I have a 1986.6 928 S. Trying to figure out, what is the correct battery size. 86.5 have the same size like a 87? Are the 86 and down different size?
Thanks in advance

Jerry Feather

Open up the box and measure it, paying particular attention to the depth. You want a 12 volt battery that is not so tall that the top posts will contact the metal lid when the lid is closed. Other than that get one that is as large as possible and still fits. Just my suggestion.

dr bob

The dual exhaust pipe cars use a Group 48/H6 battery.

Betis

Thank u so much, that is what I bought. I was doubting myself, a little. Was missing the battery hold down bracket. I ordered it from 928 intl. With this size of battery, will the hold down fit>
Thanks in advance

jpitman2

As Jerry says, always fit the biggest battery that will fit, unless you are seriously into weight saving. The box is big enough for a DIN88 unit, so why would you go for anything smaller? Or did the box get smaller in later cars?
jp 83 Euro S AT 57k

dr bob

Box is shorter on dual pipe cars. Room is needed for the right side pipe to pass behind the differential and forward of the battery box.

alex70

I remember my '87 had a HUGE *** battery. What a bear. I forgot the frame size but looks like OP is all sorted out.

belgiumbarry

Indeed, installing dual exhaust on the '82 rally car i had to cut the batterie box a bit to clear that pipe and can only use a smaller batterie. ( same but shorter)

dr bob

The hold-down works while you have the correct battery and the hold-down lip in the battery well is intact. Look at the battery, and see the extra rib molded into the case across the ends at the bottom. The forward (positive end) rib slips under the lip in the floor of the battery box, keeping the battery down and back. The wedge bracket you ordered slides down the rear of the battery. The wedge keeps the battery forward in the front lip, and also holds the rear end down as it pushes down on the rear rib on the battery itself. The whole thing is quite clever in its simplicity and function.

PorKen

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