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  • Admin

The Optima battery is a good one IMHO. Lighter and gel filled. I have seen them in Costco here for $99 (USD).

Now the bad news -- it only comes in one size -- which means you will need to make a mounting plate to secure the battery in your car. I am attaching below a PDF from a guy that wrote up his experience in the San Diego Region PCA newsletter. He made a mounting plate and changed the cable (as the old one was too short). I wonder if the longer cable would be needed if the mounting plate were made to more center the Optima in the original battery position? --- Ah, another project I haven't gotten to yet...


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I think the one to try would be the Optima Model 34R Orange Top Reverse Post Battery (same specs as the 34/78 used in the article). It seems like it might solve the cable issue since the posts are on the correct side. You would still need to make a mounting plate though.


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Interesting stuff on the Optima battery. How much lighter than stock is the Optima? What's the amp/hour rating? If gel batteries are superior to lead/acid batteries, why aren't the car manufacturers using them? Is there any other downside to the gel batteries, other than that they are hard to fit in our cars (shorter life, less power for auxillary functions other than starting, etc. ?)

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Specs on the 34R Reverse Post Orange Top (identical to the 34/78 Red Top):

Volts: 12

Amp Hours: 55

CCA @ 0° F: 750

CCA @ 32° F: 980

J240 Life Cycle: 10-12,000

Deep Cycles: ~50

Reserve Minutes: 104

Physical Size L" x W" x H": 10 x 6.8 x 7.8

Weight Lbs.: 38.8

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What do you mean the orange top has reversed connections for the wires? I looked at the article you sent me, it doesn't look like the wires cross with the red-top, so, if I used the orange top, then the wires would cross, right?

I think he needed a longer cable because the plate he made didn't mount the battery in the centerline of the car, but offcenter, necessitating a longer passenger side lead. Am I correct with this??

This is very confusing...

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Mike, it weighs about 13 pounds less then the factory OEM battery. I installed one in my cab.

Thanks, Kevin. From your experience so far, any downside to this battery (other than the installation issues) ? Power top won't work, headlights are dim........ :P

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If you look at his pictures... the original (Porsche) battery has the positive terminal on the passenger side of the car closest to the windshield. When the guy in the article mounted the Optima Red Top battery the positive post was still on the passenger side but to the trunk side. So, my point is that if you got the Orange Top Reverse Post battery the posts would be in the original postion (passenger side - closest to the windshield)... perhaps allowing you to use the existing cable. Or maybe it is still too short... we won't know till we try ;)

BTW... I agree with the centering of the battery on the plate.

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I got it now!!! Woohoo!!! I understand exactly what you are saying, thanks. I checked all the local costcos and BJ's and all the other wholesale warehouse stores, no one carries this battery in my area. So now, the next challenge is finding the battery, haha.

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Thanks for all the help, I appreciate it.  One more question, where did you find the nice red battery cable.  You had said you needed a longer one, where did you get it?  Did it come with the battery?

My local battey shop had it.. Im sure Pep Boys or any parts place like that would have them..

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I installed mine by drilling 2 holes in the battery mount plate and the base of the Optima. It's mounted about center of the plate and didn't need a longer terminal cable. I used a couple of 1/4" bolts to secure the battery to the plate. It was pretty easy. Only issue would be that I need to remove the battery mount plate anytime I need to remove the battery. I'll take pictures if anyone's interested.


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