Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > Porsche 911 Technical Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered
 
Join Date: Dec 2009
Posts: 306
Correct group size battery for my 911

Anyone know the correct group size battery for my 77 911. Someone has put the wrong smaller size low cold cranking amp battery in it. I had a 78 3.0 911 sc years ago that had a very large heavy high cold cranking amp battery in it which I think was the correct group size but don't remember it.

Old 10-30-2019, 11:09 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
Join Date: Oct 2018
Posts: 1,018
I recently went through this for my 911 SC; thread here

However, I do NOT know if a 1977 uses the same size.
Old 10-30-2019, 11:20 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered
 
Join Date: Jun 2017
Location: doylestown, pa
Posts: 699
jack olsen has a whole thread about small batteries.

i ran a SMALL <10lb battery for a while with no issues on my 76.. im not running a pc680 and its fine.

drop the boat anchor and save some weight
Old 10-30-2019, 11:55 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered
 
Join Date: Oct 2008
Location: Denver, CO
Posts: 3,494
LCOX -- seems there are 3 schools of thought here -- 1) stick with the stock (boat anchor) group 49/h8 battery, 2) go with the slightly smaller group 48/h6 battery that will fit in the standard battery tray w/o modification, or 3) go with a much smaller battery (eg oddest pc680).

On my cold weather-driven 86 targa, I went with the second option several years ago and have no regrets -- plenty of power to crank start in sub-zero weather and a fair bit easier to install than the group 49 battery it replaced.

What size is currently in place in your '77? Regardless of size, STRONGLY recommend going with an AGM-type battery to avoid issues associated with outgassing on std lead acid batteries
Old 10-30-2019, 12:16 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered
 
Join Date: Nov 2017
Location: Houston, TX
Posts: 870
I put a group 51R in to start my 78 SC motor and it's been fine for over 2 years. Needs a trickle charger if not started for about a month (same as my 993, which has a huge battery).

I've had one in a 300zx with no issue for 4 years, no trickle charger needed.

That same size battery is used in Honda Civic, Toyota mr2, small Nissans.

I live quite a ways South of the Mason Dixon line, here batteries die from heat not cold. Ymmv.
Old 10-30-2019, 12:58 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Speed Metal Army General
 
Join Date: Apr 2012
Posts: 457
The odyssey pc925 is a great option. Smaller lighter and still has tons of CCA. Not one of the super small ones mentioned, but a good in between. Mine has been working great.
Old 10-30-2019, 09:19 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Registered
 
stevie 77 930's Avatar
 
Join Date: Jan 2008
Location: Chatsworth, CA
Posts: 1,023
Garage
Lot's of info on this thread ....

Interstate battery still available for SC?

__________________
1983 911SC
1977 930 Turbo (again)
2018 GTS
2023 Audi A4
'74 914 '76 911S '72 911T '73 1/2 911T '77 930 Turbo (all gone)
Old 10-31-2019, 07:36 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Reply


 


All times are GMT -8. The time now is 06:00 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.