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I have a 997.1 GT3 and I already had the original GT3 (Moll 80-Ah) battery replaced twice. Not too bad for 9 years. That being said, Moll is a very high maintenance battery. During these 9 years, it's always being hooked up to a Porsche battery maintainer (PBM) and I had to check the acid fluid level on a regular basis. It's time to replace the battery again and I got tired with the maintenance so I wanted an AGM. I have checked other brands such as Odyssey, Bosch, Kinetik, XS Power, Exide and more. Only Banner & Exide offer 80-Ah as recommended by GT3s. Since SunCoast offers Porsche OEM Banner 80-Ah at a great price, I went with them. They shipped it fast and well packaged in a box. Installation's a simple DIY and took only 10 min. Like others mentioned before, the 'venting hole' was on the other side or on the negative side and the venting tube was too short to reach it. Since AGM batteries are sealed and no venting's required, I did not hook up the venting tube and so far no problem at all. I still hook it up to PBM nightly with no charging or compatibility issues. A fully charged battery is always a happy battery. I highly recommend getting both the Banner VRLA & a PBM as this combo will last this battery for long time.
I also had to use Durametric to clear some codes as well as air bag light after new battery.
Most AGM batteries (Bosch, Interstate, etc.) need to be vented and have vent outlets on both sides of the battery. I have the Bosch AGM H7/94R - great battery, 4 year replacement warranty and good price if ordered from Pep Boys on line and then pick up at store. Sounds like you got what you wanted but you might want to check the positive side to see if there is a vent outlet with a plug in it. - Suncoast picture looks like there might be one.
When I changed mine, I went with the Optima. For one, I've always had good luck with them and they've lasted beyond 5 years each, and two, I wanted a smaller battery as it gave me a place to install the Secondary compressor and control module for my Cargraphic front AirLift system and keep everything hidden under the plastic trim panels in the Frunk.
I've been using the Optima for 3 years and a Battery Tender maintainer with no issues. Also put an Optima into my other 997.1 and it's been fine for 2 years with a CTek maintainer.
Most AGM batteries (Bosch, Interstate, etc.) need to be vented and have vent outlets on both sides of the battery. I have the Bosch AGM H7/94R - great battery, 4 year replacement warranty and good price if ordered from Pep Boys on line and then pick up at store. Sounds like you got what you wanted but you might want to check the positive side to see if there is a vent outlet with a plug in it. - Suncoast picture looks like there might be one.
The Banner does have holes on each side. The hole on the + side has a white plug in it, which is what you see in the picture from the Suncoast website. This is the side where the venting tube used to connect to the Moll battery but cannot on the new Banner because of the plug. The white plug is really tight and cannot be removed easily. Tried to use a tool with a small hook but I was afraid it might rip into pieces which could fell inside the battery chambers IF there's an opening. The hole on the neg side can be connected with the venting tube BUT: 1. the venting tube is too short to reach the neg side and 2. it's blocked inside and a dead end with no holes or access into the battery cells or chamber. That makes me think that hole serves no purpose except to connect the dummy venting tube.
I believe the venting tube connecting to the Moll is to drain excess fluid if too much was added during routine maintenance. The Banner or AGMs are sealed maintenance-free with no acid or fluid in or out, the venting tube will not be needed. The build-up of H2 gas during rapid charging usually vents or escapes thru cell caps on Moll and special valve on Banner or AGMs. These small amount of H2 gas combine with air to dissipate rapidly and will not cause any problem. Since the battery compartments in Porsches and all other cars are not sealed or air-tight, we don't have to worry about trapping of H2 gas. The gas-escape valve on Banner or AGMs are one-way valve and will not spill any acid or fluid. Thus these maintenance-free batteries can be installed in any orientation and also safe for any transportation.
I recently installed an Interstate battery which is wider than the original however it fits with in the battery tray.
The hold down screw hole in the tray is covered by the wider battery. The shop gave me the same numbers as the battery shop, so how does this actually work?
I recently installed an Interstate battery which is wider than the original however it fits with in the battery tray.
The hold down screw hole in the tray is covered by the wider battery. The shop gave me the same numbers as the battery shop, so how does this actually work?
You mean longer not wider - wider won't fit in the tray. The correct size is a size designated as 94R/H7 - it is the proper width, height and length and utilizes the threaded hole for the hold down clamp. Sounds like maybe you got an H8 - same width and height as H7 but longer and will cover the threaded hole. Many folks use the H8 size but have to modify the hold down clamp by using bolt/nut setup in the outermost hole in the tray. If you don't want to do that go back to the shop and tell them you want the correct size. Here's the Interstate choice:
MEGA-TRON PLUS 94R/H7 AUTOMOTIVE BATTERY SIX-YEAR PERFORMANCE 790 CCA
Last edited by jhbrennan; Dec 15, 2016 at 10:35 AM.
You mean longer not wider - wider won't fit in the tray. The correct size is a size designated as 94R/H7 - it is the proper width, height and length and utilizes the threaded hole for the hold down clamp. Sounds like maybe you got an H8 - same width and height as H7 but longer and will cover the threaded hole. Many folks use the H8 size but have to modify the hold down clamp by using bolt/nut setup in the outermost hole in the tray. If you don't want to do that go back to the shop and tell them you want the correct size. Here's the Interstate choice:
MEGA-TRON PLUS 94R/H7 AUTOMOTIVE BATTERY SIX-YEAR PERFORMANCE 790 CCA
Yep. I glued a nut onto the bottom of the outermost hole. Just to hold it for the bracket and bolt. My PepBoys' Bosch H8 fits perfectly.
I can get really cheap wholesale pricing on AC Delco batteries, so I am running them in all my vehicles and so far I am having great success with the brand.
I will spend whatever it takes to get the best parts for my 997, just curious if anyone has tried AC Delco?
Their application chart specifies a Group 49 battery - it appears they do not make the 94R/H7. The "Professional" line battery has 825 CCA
I can get really cheap wholesale pricing on AC Delco batteries, so I am running them in all my vehicles and so far I am having great success with the brand.
I will spend whatever it takes to get the best parts for my 997, just curious if anyone has tried AC Delco?
Their application chart specifies a Group 49 battery - it appears they do not make the 94R/H7. The "Professional" line battery has 825 CCA
Thanks
The 94R/H7 is pretty close to the BCI Group 48. Group 49 is equivalent to the H8 which is the same W and H as the H7 but about 1.5 inches longer. It will fit in the tray but you may have to modify the hold down clamp.
Brand spanking new Porsche owner. Had my battery die on Wednesday night. I just bought the car and there is a 3rd party battery in it. Porsche dealer says to only use OEM parts, including the battery. After reading this entire thread, I'm inclined not to. How do I know exactly what battery to get for this year/model? I'm getting different recommendations from the battery selector tools at pep boys, interstate, etc. Thanks in advance from this newbie!
Bosch AGM from PepBoys. 94R/H7 is the proper size. PepBoys has a discount available on line. Great battery with excellent warrant. Fits perfectly. 10 minute installation. Stand in the frunk and save your back. Be sure to avoid contacting metal when you remove the battery cable. I slipped a rubber glove on each as I removed them. Install the small tube in the same hole as the old one. The dash lights will go out in a mile or two of driving after installation. Lots of great instructions in this section of 6speed.
Plus make sure you don't reverse the polarity on hook-up by putting battery in backwards (it has happened). Positive to passenger side and negative to driver's side. The Bosch AGM has vent outlets on both sides so make sure the outlet on the negative side is plugged then the vent tube goes in the positive side outlet.
