Lightweight Battery? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

JEDD · 01-21-2019, 04:57 PM

Has anyone used or experimented with a lightweight battery? If so, are there any common problems associated with these batteries? It seems like a pretty easy way to shed some bad (i.e., high) weight.

Quadcammer · 01-22-2019, 02:52 AM

I run an atv battery from pepboys. Same thing as thry expensive brands. Cost me 65 bux, weighs 14lbs, and starts the car better than the normal battery. Cant expect it to run any acxessories without engine running or to hold a charge for more than a few weeks while hooked up but otherwise im very pleased

swmic · 02-06-2019, 05:11 AM

Quad - Do you happen to know the CCA of the ATV battery?

Quadcammer · 02-06-2019, 05:41 AM

I believe its about 220CCA. Starts my boxster with 15w-50 oil in 35 degree weather with zero problems. As I mentioned, it starts better than my large battery for some reason.

thstone · 02-06-2019, 03:41 PM

I have used an Odyssey PC925 and the Odyssey PC680. I've the PC680 in the car since 2016 and it works great.

I replace the battery as a maintenance item every two years since my car tends to sit in-between races.

Installed pictures here: Weigth loss: Battery

itsnotanova · 02-07-2019, 02:41 AM

I installed a Miata battery in my 3.4 street boxster and had mixed feelings. It was much lighter but would only last a few months before going bad. As time went on it had a harder time starting the car. I eventually put a factory sized battery back in my street car. I took the battery I removed from the street car and put it in my rallycross 2.7 boxster and it works great. The rally boxster is gutted with no AC compressor. The miata battery starts it right up without any hesitation.

specboxCO · 02-08-2019, 10:33 AM

I've used a Battery Tender BTL09A120C in my racecar for a while now and found it very reliable. 120CCA and 9ah, not going to get the job done for a street car, but works great for me.

Boxstard · 02-10-2019, 05:36 PM

I run Deka ETX-30L, weighs 21lb, half of my original, and it started the car when it was -17F last week after parked outside all day at work. It is cranking slower in the past a few week so just hooked it up on the charger, cranks strong now. It is rated 400CCA and 28AH, if I recall, no problems for daily driving, hopefully lasts a few years at least.

Stroked & Blown · 02-10-2019, 07:07 PM

I have an ETX-30L as well and am surprised at how well it works. I figured I would need to keep it on a battery tender regularly and jump start it in the cold, but it can go weeks between starts in the summer and cranks well in the cold.

jsceash · 02-10-2019, 10:22 PM

I feel pretty good about the PC925. Mine has been in for 3+ years. I keep a tender on it in the winter but all summer long no issues, starts great good in traffic, or at the track. the post Thstone quote has some good info.

Geof3 · 02-12-2019, 10:28 AM

What does the "stock" battery weigh? I'm intrigued by the Odyssey PC925, not much more expensive that the stock unit. I keep mine on a tender all the time anyway.

Jgkram · 02-12-2019, 10:55 AM

I too switched to the PC925 about 2+ years ago and have not had a bit of trouble in starting the car. If I remember I saved about 22 lbs over the weight of a "stock" battery. I would recommend.

Geof3 · 02-12-2019, 09:00 PM

Quote:

Originally Posted by Jgkram

I too switched to the PC925 about 2+ years ago and have not had a bit of trouble in starting the car. If I remember I saved about 22 lbs over the weight of a "stock" battery. I would recommend.

Damn, 22lbs? That’s crazy. What an easy way to drop some weight. Way easier than dropping the AC system!

and probably more weight dropped!

Jgkram · 02-13-2019, 02:15 AM

Yep, sounds crazy right. The P.O. had put a huge AC Delco unit in and the darn thing was over 30+ pounds. At the time I couldn’t believe it. The PC925 unit has worked like a champ though.

SCCA_AX · 02-13-2019, 04:52 AM

There's also ~3lb lithium and LiFePO4 batteries out there if you want to go super duper light. Just read up on the alternate chemistry needs before you jump. I think Porsche offered a lithium battery as an option for some insane amount of money at least for a little while.

I've used a PC680 before and it worked great on my 911 for several years, the hardest part was fabricating a mount. Went from a 46lb group 49 to a 15.4lb PC680 plus a lb or two for the mount.

Jgkram · 02-13-2019, 05:14 AM

For ease of attachment and removal, I just used a nylon strap with a quick release buckle which passed all the AX inspections I ever went to. It holds the battery fine and I didn't have to purchase or fabricate any metal clamp or strap. Probably not the most kosher setup but it's been working for me.

rastta · 02-13-2019, 05:53 AM

I had an Optima yellow in the car for a while until the negative post cracked off the battery. Decided to go with an Odyssey - but a regular sized battery as I have had a PC925 before in a different car and it wasn't very reliable. My battery was also mounted in the front in the trunk by the previous owner for better weight distribution.

I also have been using a BatteryMINDer Model 2012-AGM: 12Volt-2 Amp Battery Charger Maintainer/Desulfator for Odyssey, Optima and AGM Lead-Acid Batteries. I had a regular battery tender before, but this unit is far superior for AGM batteries. I would highly recommend this for any AGM battery.

JEDD · 02-13-2019, 03:51 PM

Quote:

Originally Posted by thstone

I have used an Odyssey PC925 and the Odyssey PC680. I've the PC680 in the car since 2016 and it works great.

I replace the battery as a maintenance item every two years since my car tends to sit in-between races.

Installed pictures here: Weigth loss: Battery

Hey Tom,

Where did you get the bracket for the 680? It looks really cool.

Thanks everyone for your comments!

10/10ths · 02-13-2019, 04:02 PM

Rennline: Rennline Battery Mount Kit Odyssey 680 or VPR P6 - Porsche-Rennline, Inc.

Geof3 · 02-13-2019, 09:13 PM

Quote:

Originally Posted by rastta

I had an Optima yellow in the car for a while until the negative post cracked off the battery. Decided to go with an Odyssey - but a regular sized battery as I have had a PC925 before in a different car and it wasn't very reliable. My battery was also mounted in the front in the trunk by the previous owner for better weight distribution.

I also have been using a BatteryMINDer Model 2012-AGM: 12Volt-2 Amp Battery Charger Maintainer/Desulfator for Odyssey, Optima and AGM Lead-Acid Batteries. I had a regular battery tender before, but this unit is far superior for AGM batteries. I would highly recommend this for any AGM battery.

I use the BatteryMINDer unit. Second that it is an excellent product for the $$$. I’ve used one version or another for years.