Installing an Optima Battery in a Mustang

Glen · 02-07-2003

Paul, one our AFM members wrote:

"I just went to pep boys to get an optima battery. Got the 35/75 red top. The guy was all hesitant to sell it to me to put into my 95 Cobra. He was worried about the clearance on top. Also should I have a problem putting the battery in with the group 78 adapter in my 95. Thanks for the help."

I thought it would be good to post this for other who might have the same question.

Dear Paul:

Slide the battery all the way towards the passenger compartment in the battery tray so you have the maximum amount of clearance.

The battery fits tight with the hood clearance, but does NOT penetrate through the under hood insulation. The terminal closest to the hood is the negative terminal and will not short, even if for some strange reason contact is made with the hood. But be sure to put the plastic terminal cover back on for safety.

The real concern is that it does not hit metal and dent the hood. I have installed this battery in my 94, 96, and 2000 and have never had that problem. And I know of at least 25 other people that have done it with no problems. 94-98 are the tightest. Just make sure before you slam the hood shut, push it down by hand and test it for clearance.

The group 75 hold down (adaptor) is the prefered hold down. Better known as the puck.

It is a tight fit on 94-98 for sure, but this size Optima battery really does fit well. Much better then the bigger Optima. You will be glad you did it!

I hope this answers your question.

Mana4Real · 02-09-2003

That's something I should look into myself.. I could compare the physical size of and optima 34/78 to the 35/75 and then to our stock 58R group size. I believe it's a 58R stock. If I got time at work I'll check it out to see what the actual dementional size differences are.

Glen · 02-10-2003

The BCI group size of the factory is a 58. The 58R is the same thing only with the terminals reversed.

I can get the dimensions of the 58, optima, etc. if anyone is interested. I own a battery company, so it's easy for to look up

dracko712 · 02-28-2003

This is true... the optima yellow in my 90 GT hit the underside liner until I rotated the battery and slid it towards the passenger side. It is now fine.

There have been no issues on my 94 GT with the red-top optima.