I have a stock V8 flattie in my F3 that I am converting to 12v. The good folks at a local parts store were trying to tell me I needed a special order $185 battery for my truck. I guess I must have looked stupid to them or something.

I am wondering what those of you who have done a 12v upgrade are running for a battery and what is your amp output rating?

Thanks!

 

the biggest battery that will fit :P

no seriously, that is what I do with all my oldie used when I don't have a specification.

I think it was a "group 79" that worked for the cables on the correct side and box dimmensions and all, so I bought the biggest CCA rated group 79 you can get at costco - price difference was like $5 between the lowest end and the biggest end.

If you really need me to look, I will look when I get home and confirm what group and CCA it is. (mine's the 6 cyl, so the battery is on the drivers side)

And you definitely don't need anything "special" but understand the days of the $75 battery are gone, it was $115 for the cheapest and $120 for the bigger model - expect to plunk down $100 starting.

 

Brian's probably right about the cost. I don't think you can go wrong with an Optima Red Top. 800 CCA... certainly not cheap, but it's a fine battery.

Optima 8002-002-FFP RedTop Group 34 Starting Battery

 

I have a AutoZone Duralast Group 24 as I recall. 580 CCA. I just realized it's 8 years old! It was $60.

I don't think you need to go overboard with CCA, flatheads are easy starting engines.

 

group 79 must be my car - just googled it... side post, and yeah after 3 returns under warranty with GM I skipped the out of warranty GM battery and went with costco for it to.

Group 24 looks right, top post positive on the left - looks tall, but like I said measure the tray, go to costco with a tape measure in your pocket and verify. For the 6, I went with the negative on the left since the ground strap was/is shorter and it needed it set up that way.

 

Thanks guys for the fast replies.
Brain, sadly my nearest Costco doesn't carry auto batteries, I actually went there last week. I have an Auto Zone Duralast in my car, which is used VERY infrequently, and it always cranks strongly - looks like I can get a battery the right size and orientation for $85. Rated at almost 60 CCA,, it'll be more than sufficient to crank the old girl to life!

Thanks again gentlemen.