I thought I would share my experiences with installing an Optima Battery in my '76.

After reading about Optimas on this forum, I ordered the Red Top, Model 34R.

I got it from www. 1st-optima-batteries.com.

It cost $134.95 with free shipping.

The battery came with a Group 78 adapter, and two Group 65 adapters.

On my first try, I found that the battery was too long to fit in the battery tray of my car.

After some helpful tips from Tod914, I was able to install the battery easily.

Out of the box, the 34R was about 1/2 inch too long. Per Tod914's suggestion, I used a coping saw to cut about 1/4 inch off each of the four (4) extension tabs on the base of the battery. I smoothed out the cuts using a file.

I used one of the Group 65 adapters on the back side of the battery base. This adapter is a "tab" that allows the battery edge to fit under the battery tray lip on the right side.

I then used the Group 78 adapter in place of my stock battery hold-down, and bolted it in place.

If anyone is interested, I can post some photos of the adapters.

Time to go for a ride!!!!

Yes, photos please... been considering this addition...

Perhaps the battery box changed, but a Group 34 Optima dropped into my '71 with no modifications to anything. I even used the Optima "GM" battery hold down block. I did have to substitute a metric bolt for the SAE bolt they provided, but that was it. The '71s battery box is stock and completely intact.

I'm considering swapping to an Odyssey PC680, as it's 20lbs lighter.

What was the overall length of the battery base originaly ? I measured a red top base ( may not have been the 34R) and got 9 3/8 on the base. My tray is 9 1/2 long.

Just curious, getting ready to do the same.

Length of the 34R is 10 inches.

They show all the dimensions at the 1st Optima web site where I bought the battery.

It would not have fit my tray without trimming off the tabs.

Photos coming shortly..............

> On my first try, I found that the battery was too long to fit in the battery
> tray of my car. After some helpful tips from Tod914, I was able to install
> the battery easily.

Care to share those tips? My Optima is a tad long for my battery tray...

Skip

Jim, that's my setup. Just barely fits, but doesn't like (and neither do I) factory tie down. Aluminum bar stock from hardware store. You could powder coat it

the inner flange hold down has started to rub a hole in my Optima

has this happened to anyone else?

That's why I used the strap.

Howard,

The strap looks good and secure. How do you anchor the end of the strap behind the battery? Do you have to bend the strap to remove and install the battery?

Mike, just drilled and bolted thru sheet metal with big flat washers. Strap is a bit 'spring loaded' so when you undo bolt it sprongs out of the way. Then remove battery by sliding to the rear enough to clear strap.

Sprong. I like that word..

I use the 34 instead of the 34R (reversed terminals).

I prefer the battery terminals to be inboard instead of having a 'ground' directly above them. It is much easier to work on.

John

That's why I used the strap.


Is that the same strapping material one uses in CA to affix water heater tanks to structures for when the 'big one' does finally come?

John

The 34 and 34R are slightly different, in that the 34R has the mentioned mounting tabs on the ends, and the 34 doesn't, so the 34 fits the stock battery tray without modification, but has the terminals backwards from what you would like.

Using the modified 34R seems to be the best way to go if you're using the Optima. Great battery- I had one last 10 years on my 914-6.