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I broke down and bought an inductance tester... Those things are great because they take the guessing out of the game, they power from the target battery and you input the type of battery it is, the expected CCA, and you get a verdict : this battery is good, it's crap, it needs recharging but it's good... If you expected 900CCA and get 450 you know it's a dud.
I tested it in my garage and my neighbors, it told me we had 2 definitely failed batteries, one still good but low and rechargeable... previously all 3 were testing "fine" on a load tester and caused hours of misdiagnosing since the load tester passed them. Sure enough we replaced the bad batteries and all was well.. Goes to show you sometimes you need better tools... Ironically my porsche battery is/was fine, just low... I really think these cars are simply giant power sucks and the 991 should be practically tethered to a Ctek when not in use ;-(
I'm using this tester on my OEM Porsche battery which has the following written on it: 12V 70 Ah 760A EN. The tester asked me to enter the CCA but it's not on this battery. So what did you use as the reference point when the battery is brand new? Is it the EN? What is that?
I'm using this tester on my OEM Porsche battery which has the following written on it: 12V 70 Ah 760A EN. The tester asked me to enter the CCA but it's not on this battery. So what did you use as the reference point when the battery is brand new? Is it the EN? What is that?
Timely thread, as the older 991s are now reaching the age where the OEM battteries are starting to give out. I like the suggestion of getting an inductance tester to remove the guesswork.
Hey, when and if you guys are looking for the latest in battery Technology, check our our RS-30 Lithium-Ion Battery..... We are new sponsor on Rennlist and all we do are lithium-ion battery for Motorsports uses. We are currently developing a Drop in Kit for the P-Cars that use the standard 70Ah model (usually the Banner, but theymost all have the same bottom plate mount). But it will be a drop-in mounting using the existing battery mounting system in most the 991s and other models using the 70Ah battery... no modifications needed. We expect our battery mount will be ready in about a month. Our Lithium Battery is physically smaller than the stock battery but we are making a bottom plate that matches the OEM Porshe Battery. And to top it off this battery WON'T every leave you stranded.... because it will put itself to sleep before allowing it self to go dead!. It just puts itself to sleep with enough reserve capacity to RE-START the vehicle. Check the video to understand it a bit more.
Timely thread, as the older 991s are now reaching the age where the OEM battteries are starting to give out. I like the suggestion of getting an inductance tester to remove the guesswork.
So when I ran the test on my original oem battery (dated 42nd week of 2012). It shows the following:
12.7V 615cca 740ca 340din 570en
Am I to assume that the oem is rated at 760A en? Hence according to the test it’s at 75% rated? Meaning it’s going to self destruct soon?
Hey, when and if you guys are looking for the latest in battery Technology, check our our RS-30 Lithium-Ion Battery..... We are new sponsor on Rennlist and all we do are lithium-ion battery for Motorsports uses. We are currently developing a Drop in Kit for the P-Cars that use the standard 70Ah model (usually the Banner, but theymost all have the same bottom plate mount). But it will be a drop-in mounting using the existing battery mounting system in most the 991s and other models using the 70Ah battery... no modifications needed. We expect our battery mount will be ready in about a month. Our Lithium Battery is physically smaller than the stock battery but we are making a bottom plate that matches the OEM Porshe Battery. And to top it off this battery WON'T every leave you stranded.... because it will put itself to sleep before allowing it self to go dead!. It just puts itself to sleep with enough reserve capacity to RE-START the vehicle. Check the video to understand it a bit more.
Very cool! Please be sure to post when you have the drop-in kit ready. Often what keeps people from buying an upgrade like this is having to kludge together the mounting.
Very cool! Please be sure to post when you have the drop-in kit ready. Often what keeps people from buying an upgrade like this is having to kludge together the mounting.
We fully understand the not wanting to deal with coming up with a mount for a battery...most users want the drop-in fit option and so do we. Anyway here is a CAD render of the Battery Hold-Downs... we finished the design over a week ago but have to wait on the backlog of our CNC company so we are looking at 4-6 weeks to get production done.... The hold-down will be a plate that bolts directly onto the bottom of our RS-30 Battery and you just put it in like you would the original Porsche battery with no modifications necessary. We made the footer to be exactly like the stock battery so it uses the same cleat and in most cases, unless you track or race, you do not need the top hold down shown in the image. We just put that top hold-down because some race series require a metal hold down and others will be using it it for racing which has massive vibration and its and extra level of holding the battery and we also do alot of Off-Road Truck Racing and you have to have that extra level of security.
Hey, when and if you guys are looking for the latest in battery Technology, check our our RS-30 Lithium-Ion Battery..... We are new sponsor on Rennlist and all we do are lithium-ion battery for Motorsports uses. We are currently developing a Drop in Kit for the P-Cars that use the standard 70Ah model (usually the Banner, but theymost all have the same bottom plate mount). But it will be a drop-in mounting using the existing battery mounting system in most the 991s and other models using the 70Ah battery... no modifications needed. We expect our battery mount will be ready in about a month. Our Lithium Battery is physically smaller than the stock battery but we are making a bottom plate that matches the OEM Porshe Battery. And to top it off this battery WON'T every leave you stranded.... because it will put itself to sleep before allowing it self to go dead!. It just puts itself to sleep with enough reserve capacity to RE-START the vehicle. Check the video to understand it a bit more.
Love to have one of these when you have the mount on market - is the product life cycle and performance - street with occasional track use- similar to lead acid batteries?
Love to have one of these when you have the mount on market - is the product life cycle and performance - street with occasional track use- similar to lead acid batteries?
Hey Chris,
A quality lithium cell pack is actually well beyond Lead/Acid in Life cycle in this Starter Battery use. For example a Grade A lithium ion Cell is rated from 2000 to 2500 cycles whereas a top-quality lead acid battery is rated at 750 to 1000 cycles. So theoretically you getting over twice the lifespan with a lithium battery. There are variables within that lifecycle depending if there's massive heat or freezing temperatures but those are the anomalies that would affect lead acid in a similar manner. I can tell you that we expect a solid 6 to 8 years out of the battery, and being we have one of the most advanced battery management systems on board that prevents the battery from ever being discharged, which is the #1 cause of battery damage, we expect to reliably hit that 6 to 8 year mark and maybe longer.
QUOTE=Chris C.;14913356]Love to have one of these when you have the mount on market - is the product life cycle and performance - street with occasional track use- similar to lead acid batteries?[/QUOTE]
Thanks again to daberlin for wonderful write up. Followed exact instructions & was done in 30 minutes with zero issues!
i went with the Interstate size 33 Battery. I found it at Costco for $132.00. 42 month replacement. Happy with the preventative maintenance on my Lucy!!
Thanks again to daberlin for wonderful write up. Followed exact instructions & was done in 30 minutes with zero issues!
i went with the Interstate size 33 Battery. I found it at Costco for $132.00. 42 month replacement. Happy with the preventative maintenance on my Lucy!!
This is a great price for an Interstate Battery, including maintenance free. I too previously purchased the same battery only to find it’s not an AGM rated battery and returned it. I ended up purchasing an AGM Interstate Battery from a local auto shop but at nowhere near the $132 price offered by Costco.
I discovered the Interstate Batteries cover the battery compartment completely and weigh much more than the OEM Banner Batteries. In all, I’m satisfied with my decision.
03-25-2018, 03:26 PM
