Red Top Battery Question

[rocksteady_racer]

I have an Optima Red Top about 2 years old. It wasn't starting my 90 240 so I pulled it out and put in my brand new miata sized battery prepping for the turbo install. So now its running fine. So since I wanted to get my 91 240 running (all it needs is a battery and some seats so I can limp it down to my garage and replace the trans), I decided to charge it up to see if it was ok. I checked the voltage on it after sitting for about a month = 12.4V. So I started charging it. why wouldn't the 90 240 start with a 12.4v charge? The battery just needed a little bump maybe?

[4cefed]

Or the battery terminals weren't making good connection until you swapped batteries.

And, just because it's reading good voltage doesn't mean is has the a** to keep that voltage while cranking. Try putting it on a trickle charger for a couple days, that might help it. Optimas are tough to kill, I had one for over 7 years.