Have a question for you guys.Would like to take a poll.What is the strongest 6 volt battery out there?. I am done with Delco batteries for the ol' Chevy.
Commercial 6 volt are larger at 13.5 inches allowing them to really deliver the amperage for both starter and ignition. you just need a little more room to accommodate them.... http://www.jalopyjournal.com/forum/showthread.php?t=640604&page=3 .
optima makes one http://www.amazon.com/Optima-Batteries-8010-044-Starting-Battery/dp/B00099HVN6 Edit: ck out this thread it talks about best cranking 6v batteries from napa on page 3. http://www.jalopyjournal.com/forum/showthread.php?t=640604&page=3
When my car was 6 volt I had an 8 volt battery in it. Worked well, just had the regulator adjusted up a bit.
I have had an Optima in my '51 Ford for the last 6 years and have been very happy with it. The one I have is 800 CCA. I have two caveats : 1. Make sure you buy it from someone who will honor the warranty. There have been complaints about quality control lately (do a Search) and be prepared to pursue proper warranty remedies. 2. Make sure you know about the special charging requirements; a regular charger won't bring a dead Optima back; you have to have a separate good 6-7 volt source to "get it going". Also, I would recommend against an 8 Volt battery. They are nothing but a band-aid for bad grounds, deficient cables, and bad connections. If you should inadvertently correct one of your existing problems, you will be buying and replacing a lot of lights bulbs. IIRC, if you happen to have a "Wonderbar" radio in your car, 8 Volts is very hard on them. They were made for tractors with simple electrical systems and no accessories.
I'm running an 8 volt in the Reo as well....no issues at all, didn't even have to adjust the regulator. Starts great. 6 volt maintainer over the winter, it's been a couple of years now and still no issues.
I forgot to mention that there are kits available with a dummy top that allow you to put an Optima diagonally in a gutted stock case. They look pretty good when done.
optima. great batterys. if i replace a battery they are all i use. buy it at orileys or advanced auto. its on your account no promblems with the warrenty. if you let them go completly dead then you will need to connect with another 6 volt to get juice back to it. but if it is just low. a 2 amp charge works great. dont do the fast charge. they are expensive but they are well worth it.