After 3 1/5 years and 52,000 miles, my OEM battery finally started giving up the ghost. I replaced it with an Interstate MegaTron Plus 40R. I thought about an Optima, but couldn't justify the price. No install hassles, after removing the side spacers, the Interstate fit like a glove. The first day below zero, car started like it was July.

 

Did you replace the battery insulation blanket or throw it away?
The price will justify itself in a few years time.

 

The insulation blanket wouldn't fit the 40R size Battery

 

Yikes
That will shorten the life even quicker.

 

Glad it works well for you!

 

I think my battery might be going. I'm getting a dead miss on cold starts. Like the battery goes down too low a voltage to fire a coil or two, but just for a second until the alternator brings it back up. Does that sound like a resonable theory to anyone? It doesn't seem to do it except the first start of the day on cold days~40 degrees or below. Not throwing any codes but you can definately feel it miss once or twice.

 

The voltage thats required to fire the plugs is a lot lower than the
voltage required to turn the starter. If she is cranking at a normal
speed, the voltage would be great enough to fire all the plugs.
They older vehicles had a ballast resistor to compensate for low
starting voltages. The S197s do not.

 

I will probably make a new one before hot weather

 

And no fear that the increased battery size will overtax the alternator
and cause snowball effects on the charging system? Maybe you need
to replace the alternator as well with a high output modelto support
the bigger battery? Hmmmm...

 

No, the 40R is the recommended high capacity battery size in the owners manual. The OE battery was 500 CCA, the new one is only 590 CCA - not that much bigger.