dertub

Time for a battery change in my ‘11 GT3 RS 4.0.
What is the best? Antigravity? Lightweight would be preferred.
I’ve been told to stay away from Porsche batteries.
Please only reply if you have actually installed one.
Thanks.

flyjets

Antigravity

CME

^^^

Group 48; 30 amps I believe. You just missed the sale.
Chet

dertub

Thanks.

usrodeo4

997 4.0 GT3 RS? That is pretty much the Holy Grail for most driver involvement in the 911 model. I tip my hat....my target someday car is the 2011 GT2 RS. There happens to be one for sale out west right now for $384 that has me thinking
Used 2011 Porsche 911 GT2 RS Coupe for sale in SCOTTSDALE, AZ 85260: Coupe Details - 585760334 - Autotrader

GrantG

Awesome car, but I'd say it's only the winner on driver involvement among water-cooled 911's

Antigravity

As an FYI, we did a PRE-MEMORIAL Day sale because we did a special email blast with Rennlist, and a Home page take over with a bunch of our Banners on the Rennlist Home page.... BUT we still are going to have a normal Memorial day sale, but it won't be advertised on Rennlist since we did this early sale so we could tie it in with the Rennlist email and such...

So on the 28th we have our regular Memorial day sale and you can get the deal then...

Sword_of_the_Spirit

I’d recommend EarthX. I’ve been using them since ‘16. Etx24c. Less than 3lbs. You could opt for the 30 and be fine. I think you’ll need a custom box or you could make one yourself. Either way, well worth the effort. Oh, and pay for it with a Costco Citi visa for extended warranty peace of mind if needed.

Antigravity

Hey Sword, and Dertub, EarthX makes a fine battery, but you do not want to use a ETX24 size battery in a Modern Sports Car in general. Yes I understand Sword has had good luck with it, but that is a 7.8 Amp Hour Motorcycle Battery. 7.8 Amp Hours is not enough battery capacity to deal with a car that might need to turn on emergency lighting in the event of a roadside emergency, nor can it handle cold weather well, or if discharged a little won't always get the start, and finally it really cannot hold a charge very long if the car is not driven very often or sits a little while in the Garage. But EarthX does make larger Amp Hour sizes so you could look at those, but when using a Lithium and not wanting to do any extra charging or maintenance, the minimum size for a Car used on in a Street driven Car and not as a Track Car only should be about 30 Amp Hours to be able to use as a direct replacement for a Standard 70Ah Lead/Acid Battery the Porsche comes with. Minimum 40Ah is the best and 60Ah if you live in colder climates or need more storage time, or have more aftermarket accessories.

For racing and track only a 7Ah to 10Ah battery can work in some circumstances, but if you have a lot of fans or other stuff going after you come in from the track that might not be the best either. But we are aware of many who do this, I'm just saying overall for no-hassle use of a Lithium in a Street Car make sure you have sufficient amp hours or you will have to monitor it much more.

Sword_of_the_Spirit

Get out of here Scott. You made your pitch

Antigravity

Hey Sword, I'm not scott, we have a few of us techs from Antigravity using this account who respond to questions on the forums. I don't feel I was making a pitch, but rather just posting up some important considerations when using Lithium Batteries. You can write directly to Scott (President of AG) if you think I was overstepping. His email is in the signature for the company below.

Sword_of_the_Spirit

All hypotheticals posted by you or someone else. I would have expected numbers or some evidence lending credence to your post as a tech. For a company that I quote, “sells thousands of batteries a month,” where is the evidence on excessive battery drain from using a product I recommended and have used? You post nothing but hypothetical and biased “what-it’s.” A company as astounding as Scott and others allude should make this quite short for us here on Rennlist. After all, Scott unequivocally stated there isn’t a more prolific litho company in Porsche’s than you. Can you tell me the draw from a radio on 997gt3? How about running the fans (radiator) for 10min after an event while vehicle is off? Or even better, power differentials from a 7ah to your large automotive battery necessary to turn over a mezger block when under 40 degrees?

mooty

I prefer the heavy OEM battery for street cars.

JB911

I got the largest AGM Bosch since I don't track. The day I need to replace it I'll probably get this Odyssey

https://www.odysseybattery.com/produ...attery-49-950/

Antigravity

I guess I have offended you, didn't try to do that. I was just trying to say that a small 8 Amp Hour Motorcycle Battery in a Modern Era Porsche is not the best choice. If you read my post I said "in general its not a good idea". I explained it can work for some people but you will have to watch or maintain the battery much more and that is an accurate statement. I can't give you specific draw numbers on a 997 GT3 RS, nor really many cars because that can vary greatly across all cars depending if you have aftermarket accessories like Camera, Radar Detectors, USB plug in devices, Bluetooth devices and even temperature. But in general there is a baseline Amp Draw on 997s as in most all modern cars due to electronics.

But what I can do is give you some general facts that just solidify my point so you understand I"m not attacking your stance but rather just giving the people who read this a better understanding of Batteries.

Porsches come stock with a 70Amp Hour or 80Ah Battery in their Cars... so there is a reason that the Engineers did that for that... Its due to having enough capacity to run electronics, lighting in case of emergency and have overhead to cover leaving the lights or stereo on when kicking back in the car. It is also for decent storage time in the Garage and good Cold weather starting. So an 8 Amp Hour Motorcycle Battery is not capable of offering that so it is not something Porsche nor any Auto Manufacturer is going to recommend except perhaps is a race or track only use. It is sort of like offering an Pint of water as reserve when they normally get a gallon of water

Porsches have Electric Power Steering, and also some have Rear Assisted Steering as well, additionally in the Sport Modes they draw more current than driving in Normal modes and when those modes and functions are all turned on the amp draw from these devices goes up substantially and can in fact draw more current that the alternator can put out quickly, so a larger battery assists in meeting that higher current demand and supports the alternator for a few moments. But if the car senses a voltage anomaly like undervoltage even for a micro-second it will throw a flag, and the chance of this happening with a smaller battery is much higher since it has so little battery capacity.... This is also why you see so many flags in Porsches when the battery is low or going bad. It is because the battery no longer has the capacity to hold a voltage under load. Keep in mind I did not even put in the A/C or other models that have heated seats...

So understand you can do whatever you want personally and if that works for you great, but Antigravity is a company that is pretty conservative on recommendations and doesn't want a Customer to say we recommended a product that won't work correctly under overall typical uses, nor as a direct replacement battery when the majority of Customers are not Racers or Track people. You will not see us offering our Smaller Lithium Motorcycle Batteries for Porsches here or for other Cars unless they are Race specific because of the low Capacity and potential for Flags. Last, keep in mind your use of a battery might be only in good weather mainly where as others maybe drive in much colder climates, and you may not have aftermarket or other accessories and maybe you drive more often than others so you battery stays re-charged more often. At Antigravity we are selling to a broad swath of uses, we want Customers who can just put a battery in an forget about it and say it works great and does not require special monitoring or the potential for issues. So just wanted to explain that better.