froggy47

So after all the chit with battery/starter/shielding/etc. See other threads. I go to instruct BMW event Sunday, after taking care of my students, go to eat lunch in the car & listen to the radio.

SOB if the friggin batt is dead after about 20-30 min of radio. Are you serious? It's a spec 590 ca 800 res (IIRC) and 6 mo old. My buddy jump starts me & all ok.

Anyone get a bigger batt spec. ca/res one that will fit in the box? What? Do I have to start carrying around my jump pack every day? Chit! Chit! Come on.

I KNOW it's 7.0 liter 11/1 compression ratio. So did GM put both a starter AND battery in that is too weak? This is not fun/funny.

MTPZ06

If anything, I feel the alternator is marginal at best for our cars. If and when mine goes, a higher amp Mechman alternator will get swapped in.

froggy47

I am sure that's probably right on, considering the rest. Anyone help with a better battery?

BigVette427

Jason has a DIY video in how to get an AGM in the rear battery compartment; I'll probably do this next. The Odyssey isn't all that more powerful and it's a lot more expensive.

froggy47

Thanks that duracell has a little more ca and res.

Too-Fast

I have been using the AC/Delco Professional Series Battery for the past 10 years on my 'vettes and I usually get 6 years out of them the Z06 battery has 800 CCA and 900 CA as opposed to the Duracell 600amps. The Delco also has a 42 month warranty.

Hib Halverson

When you say, "The Odyssey isn't all that more powerful", are you sure of that?

As for "parasitic draw" Jason admits, he's actually never tested for it. My position is that ZO6es do not have a significant parasitic draw that is a design defect. The only parasitic draw, I've ever had trouble with is leaving my wide-band O2 sensor plugged in. I don't have a Mild-to-Wild modification, but I had heard some of those do draw when you leave it in one of the modes, but...those are operator problems not a problem with the battery. If I leave my wideband plugged in, it doesn't matter what battery I have, it will go dead.

That said, no modern car is completely free of any parasitic draw. In fact, GM actually specifies how much draw is acceptable, but the "acceptable" current draw is very small, ie: it takes months of the car sitting before the battery discharges to the point that it won't start the engine.

The Odyssey for a C6 ZO6 or ZR1 has a CCA rating is 540-amps, which is 60-amps less than the Professional battery the ACDelco catalog calls for in a ZO6. There are some who discount the CCA rating because it's defined as: a 30-second discharge at 0ºF. Unless the user is planning to actually discharge the battery at 0ºF for 30 seconds, the CCA rating is of minor concern. HCA is more interesting in that it's a 30-sec. discharge at 80°F, a more realistic temperature for a ZO6. The Odyssey's HCA is 860-Amps whereas the Delco comes in at only 750, 110A less, but even the HCA rating is not that important. Generally it would be unusual to have crank the engine for 30-seconds, regardless of temperature. If someone's ZO6 does regularly see 30-second cranking times, there something a lot more problematic than the battery.

The real benchmark for a battery used to start a high-compression V8 is PHCA or "pulse hot cranking amps". That rating is based on a five-second discharge typical of starting an LS7 or any other high-compression engine in a real-world situation. The Odyssey PC1200, the battery which fits a C6 ZO6 or a ZR1, has a PHCA of 1200-amps far greater than any other battery available for that application. ACDelco doesn't even publish a PHCA rating. Another advantage is an Odyssey is that, by virtue of its construction and materials, it's more tolerant of deep cycles, ie: running the battery dead or near dead then charging it back up. I have first-hand experience with the Odyssey's tolerance of deep cycling with my occasional running the battery dead by leaving my wideband plugged in.

I have an Odyssey PC1200 in my 2012 ZO6 which I installed in July of 2014. The first time I started the engine after installing it I could tell it spun the LS7 over with a little more speed. It's been in service six and a half years, in spite of my attempts to kill it with deep cycling. That's pretty darn good durability for a battery in a high-performance duty cycle which has seen some deep cycle abuse.

Lastly on the AGM "thing"...indeed, the Odyssey PC1200 is an absorbent glass mat battery.

jimbob8915

Hmm. My battery is such a non-issue I can't even remember what battery I have. I also still have the factory alternator. I have an 800 and 100 watt car stereo amplifiers that I listen to an still have had no issues that I have not had with any other car. I have had my 06Z for 7 years which is the longest I have ever owned a car and it has given me the most joy and least issues of any car I have owned.

froggy47

On Amazon for $242.


Hi Hib,

I bought the Costco (Interstate) last night (their code #37) so will give it a go. $100 bucks. The ca/cca/res are in the ball park with these other ones. If this one craps on me I'll try your recomendation, always trust Hib, knows his chit. Period. Gladly pay the premium to have reliability and put all the battery chit behind me.
I have come to my own conclusion, since there is no gov't (ugh) or independent certification on these ca etc. numbers, they are about as reliable as the tread wear numbers, or any "lifetime" warranty on anything.

Whis9

Why do you say that and what size Mechman would you go with?

Thanks

MTPZ06

I've just seen a lot of alternator threads over the years...failures, and voltage drop at idle, voltage drop under load, etc. That voltage drop can have an effect on everything...lights, fuel system, ignition coils, ecm, fans, etc. If your car is essentially stock from a power demand standpoint, the mechman 170 amp fits the bill for most. If you have some big stereo system for example...240 amp is the better choice.

It goes without saying that a battery tender is simply a best practice with these cars...but if the OE alternator doesn't do a good job charging the battery, and keeping it fully charged during operation, you can run into scenarios like the OP described in his post.

froggy47

In my case, to be clear, based on dash voltage readings the alt is doing it's job. It's insufficient batt & drains that killed it. IMO.

It was driven 25 mi to event & 4 practice runs (BMW style - instructor familiarization with course) . Shut off for 2 hrs. while I instructed in student cars. 5 fun runs next(rides for students & general hooning around) then shut down for lunch/radio music - stock radio. I do not turn off between runs. So the bi%$h was full charged when I shut it off for lunch. Just sayin.

Daily I drive it 2.5 to gym. 2 hr shut off. 2.5 back. So that scenario is not many miles to charge it up for 2 starts, still in that scenario it runs fine. So let's not swerve into alternator theories or excessive drain theories, shall we? Does have a tiny dash cam that runs/drains a small amt while parked. Motion sensor thing. V-1 detector was probably on in accessory mode. So 2 not stock drains, camera & v-1. just think most of the batteries that fit in the little box barely have any reserve. So partly blame gm for tiny battery box & partly the battery companies. This was not a case of not enough juice to spin a 7.0 liter 11 to 1 ratio engine. It was full dead. Did not think to view the volts on the dash.

MTPZ06

Well...I got 6.5 yrs out of my OE battery, and 20 minutes of leaving the factory stereo on wouldn't have killed my car. But I also haven't had the starter issues you've encountered either. Perhaps some multi-meter readings in key areas under the hood versus what you see on the dash might be in order.

froggy47

I put in a Costco/Interstate lead/acid just now, we'll see.

psp6158

You didn't mention how often you drive the car, if they sit for a day or two without being on the charger they seem to die quickly. My first lasted 5 years and I'm on my fifth with this one. I'm using battery from Chevrolet dealer bit plug it in after every drive...

Mr. Gizmo

how long does the car sit before you take it for a considerable drive or put a trickle charger on it?

from my experience with my departed 2009 z06 the battery lasted until September 2016 and it still seemed fine. I did put it on a trickle battery tender charger twice a month for 48 hours each time. I was consistent with this.

froggy47

See #13, but to repeat daily driven (short trip).

froggy47

Daily driven (short trip). see #13.

froggy47

OK, so this is not a friggin Tesla, I should NOT have to plug in a daily driven car, wife's Merc is a dd/short trip and her batt (oem) lasted 4 years. Just put in a NAPA Legend in hers . So will see on that.

To compare, my 02 Suburban with Costco/Interstate sits for WEEKS outside. Just sits. Starts instantly with 110k plugs/wires. Costco batt in that last 4+ years & I change it when it's still good for dead nuts reliability. This is my "get out of Dodge truck" if/when chit happens, load the fam in & some survival stuff tent/water/food/protection & head to desert. I do need some new tires on it, but I digress.

As stated I just bolted in a new Costco/Interstate lead/acid and will see. If it sucks going with Hibs rec. These cars eat batteries like I eat cookies. Humph.

Here a quote from an old gearhead on Quora:

IF the battery and charging system are in good condition, and the car starts up normally, meaning within a couple of seconds for any modern car in good condition, it takes only a couple of minutes or so to replenish the small amount of energy stored in the battery that was used to start the engine.

If it is very cold, and the car takes five or ten seconds to start, it will take longer, up to half an hour or so.

ALL the MODERN cars I know about, and that means A LOT OF CARS, have alternators that do produce adequate

charging current at idle speeds. In most cases they produce enough to run all the usual accessories such as radio, ac, lights, etc at idle speeds.

This is easily verified by the fact that if you watch the ammeter on just about any car or truck built in the last couple of decades, it will NOT show a discharge when idling. even with the lights and ac, etc on. Of course a lot of models come only with an idiot light, which shows only two states, charging or discharging. If the light is on, your battery is being discharged, otherwise the alternator is producing all the electricity needed.

I have jumpstarted at least a hundred different cars in the last twenty years and left them idling to recharge the battery. ( I mess around with old cars and help my friends and neighbors out free of charge when it comes around to a jump start. I get it back in other ways, such as an invitation to dinner, etc. ) In EVERY case, unless there was a problem with the battery, alternator, etc, the alternator DID CHARGE THE BATTERY AT IDLE.

Some older cars will not charge at idle, but they are few and far between these days, most of them were scrapped YEARS ago.

It a lot of cases, you can hook jumper cables to the battery in an idling vehicle to jumpstart another vehicle, and ACTUALLY HEAR the engine in the running vehicle start PULLING a little harder.

THIS is because the alternator SENSES the extra load, and starts using more energy to produce more current. This energy is supplied to the alternator via the BELT driven by the engine. The fact that the alternator is trying mightily to provide a LOT of current at idle speed , far more than normally needed, actually SLOWS the engine down a little.

This is also my same experience as old gearhead. Please post if you actually do these things, no keyboard experts who run to the dealer to have the air in the tires topped off. Thanks.

acroy

I have limited experience on this but a couple things jump out:

- batt dies when in ACC mode for 30min. Can you measure the amp draw? I don't know what it is on a stock car, and yours has radar detector, camera etc. It may be rather significant.

- I have had good luck spending the $$ on a 'marine' deep cycle batt in certain applications. Unlike traditional car batteries, they are meant to be drawn down significantly between charges.