LT1M21Vette

Time for a new battery on the '71.

Time to loose weight, get a smaller battery and go AGM.

What is the minimum amps needed to spin the starter for a 350?

I had good luck with Odyssey batteries on my other projects.

Anyone having actuall experience with Odyssey, Optima, Deka, Bosch, etc?

69427

Depends on a couple things, such as starter type (stock C3, or C4 PMGR), and how far into winter temps you still want to start the engine.

mrvette

SO TRUE, but one thing.....I have been buying Marine Deep Cycle batteries for my cars....not only cheaper, but better cranking power over longer intervals....

LT1M21Vette

Not much weight saved, unless I have deep pockets.

i3478X
13.4lbs
$1102.49



78-PC1500-A
Cold Cranking Amps (CCA) 850
49.5 lbs
USD$ 308.54

69427

I chuckle a bit at times about my battery choice, but several years ago I was scratching my head trying to figure out where I could get some extra weight out of the car when I happened to think about the battery in my lawn tractor (365CA, 300CCA, 16#, $29.95). I hooked the battery up with my jumper cables and it cranked the engine over quite well. Ended up buying one and putting it in the '69. It's on its third or fourth year so far.
For full disclosure, I rarely start the car when it's below 40* (it's not my daily driver) and I've got a lightweight C4 PMGR starter which requires less current draw when cranking. Also, being an old car, it has minimal electronics current drain during storage.

YMMV

joewill

batteries lose 10% a year in cranking amps. don't try to match amps to cranking needs. buy the most cranking amps battery you can find and it will start your car for years.

thegazman

I needed a battery for my 79, L82 late one Sunday evening. I purchased a Walmart battery as they were the only store open. The battery lasted eleven years. The DieHard I had before only lasted two years.

69427

He's trying to take some weight out of his car.

spedaleden

I've used Optima and have had it ten years. I use a battery tender in the winter but my main reason for this battery is I did not want a leaking battery loosing battery acid on fiberglass.

Just my 2 cents

C3 Stroker

I've had good luck with the Braille b3121 battery (22 lbs.) for several years now. But I don't drive in winter, only from April through October in good weather. I bought it for the sole purpose of weight reduction, while having a strong battery for the car.

This one...http://www.braillebattery.com/index....atteries/b3121

Justin@EntropyRad

Always wanted to experiment with one of these Li-Po:

http://www.all-battery.com/148volt-5...-polypack.aspx

69427

I don't see how the voltage & current charge and discharge maximums are compatible with automotive starters and alternators.

Justin@EntropyRad

Point taken...just the theory of them. I've seen where people are building their own automotive LiPo cells that are rated properly

LT1M21Vette

Looks like a good match.
Thanks!

68/70Vette

I don't think you can just replace a lead acid battery with a lithium battery. The intrinsic plate voltages will be slightly different. The stock alternator voltage regulator will, I would suspect, not work well with a lithium battery.

I noticed the lithium battery was priced at over $1000. I've read that a lithium battery is an option on at least one Porsche...the option costs about $2500. Big bucks for saving weight.

mikem350

[QUOTE=68/70Vette;1589385217]I don't think you can just replace a lead acid battery with a lithium battery. The intrinsic plate voltages will be slightly different. The stock alternator voltage regulator will, I would suspect, not work well with a lithium battery.
QUOTE]

The batteries for cars have circuitry inside that make them compatible with vehicle charging systems. Also protection for the cells.

REELAV8R

I think that is a great idea if you want to save weight. Just get the sealed one to prevent leaks and it would be fine for any warmish weather starting.
You could buy, what, 10 of those lawnmower batteries for even the cheapest light weight AGM.

Lithium batteries in a car Yikes, not me. I like this statement about them.
I suppose something similar could be said of lead acid batteries, but they are not so sensitive about discharge and charge method. Lithium has a bad habit of catching on fire when pushed to it's limits. As a bonus there is no effective way to extinguish that fire.