Ok, so the time has come to select a battery and I'm not sure which direction to head. Originally, when the 3.6 was in the black car it had an Optima Red top, but it just wouldn't perform how I wanted to, and I was just not impressed. If I remember correctly, I think it would sometimes die overnight even with a fair load/voltage, and with nothing on in the car, or sometimes it would perform badly with multiple things on in the car.

I'de like to see what everyone else uses and go from there. I suppose I'm still open to the idea of the Red top, and it's possible that that one was just old.

I've had a red-top for the last 10 years (3.6L engine). I don't know when it's going to die but it's been exceptional. But I keep it "tended" lots of the time when sitting for more than a month, and I have a battery cutoff that keeps any draw on it down to nothing when the car is at rest.

There is a yellow top that is supposed to be for cars that have more draw than just starting, but I'll replace this one with another red-top when it expires.

http://www.optimabatteries.com/product_sup...nce_storage.php

and

http://www.optimabatteries.com/product_support/techtips.php

Good luck!

Thanks for the reply, Ron. If I may ask, which Red Top do you have?

I bought my red top at costco and they will return anything at any time if you're not happy with the purchase. Good prices too.

*I bought a watch from them, broke it after 3.5 years - no receipt - they looked up my purchase, smiled and gave me cash. Yes, I'm a fan.

You're sure the problem was with the battery and not a short or something with the car?

The SC 34 U (no spaces)

I have mine up front where the stock tank goes so it might not be the proper terminal type for an engine compartment application. I also have a 4 guage grounding cable strung from that battery to several chassis points all the way into the engine bay including the fuse box etc in the cockpit.

So the battery and components don't have to fight too hard to hunt for a ground when they need it. I don't know that that helps much but I feel like a well maintained electrical system keeps me going more often than it lets me down.

Good luck!

RedTop in two cars ... start them once per week ... no problems

Generally will put them on a 2 amp charge cycle while playing in the garage on weekends ... I don't charge them for more than 4 hours.

I see on that Optima site that they recommend charging at 1 amp max... never had to do that but I've always used a trickle-charger on mine. Those AGM batteries are a bit different. The lowest charge on my Schumacher charger is 2 amps. I'd use it in a pinch.

Years ago, I've left mine for several months at a time several times (travel) and it never failed to start with no hesitation.

2 amps is as low as my charger goes.

Have a HF maintainer, but it says not to use on a AGM battery .. no reason given why, but I don't use it anyway. It has become "wall art". For $4.99 I couldn't pass up buying one just to say I had it.

Same yellow top for the last six years. No charger of any type...I haven't had to touch it even with the car sitting for 3-4 months of no use. If/when it needs replacing, another yellow top is a no-brainer.

I fab'd a 12V - .25A power supply while back in school a million years ago that I use occationally. Hmm, I wonder if it's bad for the thing? Mostly I ignore that battery. Maybe I'm just lucky!

Frankly I'm convinced the battery cutoff is a large part of it. Simple isolation. Bad for people, good for batteries... Ok, most people!

I don't have a big engine but I do have an Optima red-top. I bought a Battery Tender Jr. charger (.75 amps) to keep the battery topped off when I'm not driving the 914. The battery is 8 years old and still going strong. I think for my car a yellow-top would be overkill because there isn't much of an electrical load ..... I don't even have a radio.

Coincidentally, I was looking at Optima batteries online yesterday. Red Top is the automotive starting battery; Blue Top is the deep-cycle marine battery; and the Yellow Top is double-duty, with both starting and deep-cycle characteristics.

Sorry if I'm stating what everybody already knows.

Battery choices for our cars is sometimes a difficult thing. For those who have stock cars the (Optima) choice is simple... red top. But many of us are "outlaw" types (356 nomenclature) who have as many different individual cars as you could ever imagine.

Some of them need more battery than the original car required. Others can report on what they need beyond primary ignition. I'm thinking the Optima choice is between red top and yellow top.

That said there are other battery manufacturers out there. Let's hear from them.

Optima red top because it matches my cars paint ...

I have the red one for 4 years. I disconnect it every time I park it overnight because I have a parasitic drain from something and no time to track it down. The car sits all winter in the sub-zero temps with the battery in place. I connected it this spring and started the car. No trickle charger, no nothing.

Ive had 11 years out of a Optima red top. Ive had really good luck with Odyssey batteries. I use the PC 625 and it works good on my high compression 4 banger I know a few guys using them on v8 engines. You dont have a lot of reserve with it.

OK. Now tell us the REAL reason you bought a yellow top.

I had the red top for years as well, with a small six, no probs at all. My car would sit for weeks and fire right up. It sounds like the OP may have a battery drain either from a short or something like an alarm or stereo.

The same reason Andy bought a red top.

Small Block Chevy with yellow optima with a decent amp stereo--seems to be a good combination for plenty of umph for starting and the stereo. I do keep a tender jr. connected when I don't drive it to keep topped off. It does take 4-5 days after driving the car before the tender jr goes to "green" which is a non charge mode, just maintain. I believe my alternator is around 55 amps.

If I can only learn to turn the amp off when I'm done driving the car life would be good.

I use one of those 1-2W solar panels on my truck, the redtop in it is only 5 years old, but the alarm drains it in about a month. With the solar panel, it always starts up. Plenty of power for the 350 too.

The 9 year old redtop in my '71 just quit after cranking my new 2.0. (I think my charger was on too long.) So my backup redtop is in there now. It's only 6 years old. It's been on a 5W solar panel for a few years since I put my '74 up on stands...

Going to put the dead one on the solar panel and see if it works next year...