6 volt battery type??

[SAXBY2]

the original question was what type ? What Mr Bidonde showed, group 1, 6 volt , also fits early Porsches, VW's. Appears that the only AGM available group 1 is Optima.

 

[alexiskai]

the original question was what type ? What Mr Bidonde showed, group 1, 6 volt , also fits early Porsches, VW's. Appears that the only AGM available group 1 is Optima.

Just because he used the word “type” doesn’t mean the answer to the question is “a Group 1 battery.” From the context, you can tell he’s putting group 1 batteries in there and it’s not solving his problem. Putting an Optima in there also will not solve his problem.

 

[ModelA29]

The Optima has 800 CCA. AGM batteries require a different charging profile. Make sure your Battery Tender is compatible.


This is a good AGM/Conventional battery and charging video. Delphi was originally Delco.
https://youtu.be/TAHY2maRvUc

 

[nkaminar]

The original post was because the starter cranks the engine slowly. This probably has nothing to do with the type of battery but could be anything in the starter motor electrical circuit or in the charging system, including the starter itself.

 

[Bruce of MN]

The OP hasn't checked in with any feedback on what tips he has checked out.

My car started cranking poorly and just judging by diameter, the starter cable was 4.5 AWG, a new proper size cable made it all good.