What are differences between R79 and R89 battery

[Brad M.]

What is different between a R79 and an R89(S) battery? Are these different size or different power?

Do they look visually the same other than the obvious difference in the part number?

[Terry M.]

Re: What are differences between R79 and R89 batte

The R79S has 3/8-inch positive terminal threads and 5/16-inch negative threads. The R89S has both poositive and negative terminal threads 3/8-inch. In all other respects those batteries are the same. You may wish to review a 3 part story I did for The Restorer about the introduction of side terminal batteries. Those stories, complete with some engineering drawings, appeared in the early to mid-1990s. Check the on-line Restorer index on this site for a more exact date.

[Terry M.]

Re: What are differences between R79 and R89 batte

The R79S has 3/8-inch positive terminal threads and 5/16-inch negative threads. The R89S has both poositive and negative terminal threads 3/8-inch. In all other respects those batteries are the same. You may wish to review a 3 part story I did for The Restorer about the introduction of side terminal batteries. Those stories, complete with some engineering drawings, appeared in the early to mid-1990s. Check the on-line Restorer index on this site for a more exact date.

[Chuck S.]

Re: What are differences between R79 and R89 batte

I don't know about others, but I have found the on-line Restorer index difficult to use unless the desired information uniquely "fits" a year class. Some articles seem to fall in the cracks between year classes/topics and are impossible to find; in those cases, I simply give up and drag out the hard copies, and use old obsolete printed indices.

A recent example was the questions on black phospate processing...at least two articles have been published in the restorer. I couldn't find either of them because the topic doesn't fit "plating", it doesn't fit a single year class, it isn't restricted to any single area of the car, and the more general category of "part refinishing" doesn't exist.

An index with better organization by topics is needed, or perhaps a general restoration category which can apply to many or all year classes.

[Chuck S.]

Re: What are differences between R79 and R89 batte

I don't know about others, but I have found the on-line Restorer index difficult to use unless the desired information uniquely "fits" a year class. Some articles seem to fall in the cracks between year classes/topics and are impossible to find; in those cases, I simply give up and drag out the hard copies, and use old obsolete printed indices.

A recent example was the questions on black phospate processing...at least two articles have been published in the restorer. I couldn't find either of them because the topic doesn't fit "plating", it doesn't fit a single year class, it isn't restricted to any single area of the car, and the more general category of "part refinishing" doesn't exist.

An index with better organization by topics is needed, or perhaps a general restoration category which can apply to many or all year classes.

[Brad M.]

Re: What are differences between R79 and R89 batte

Thanks, that answered my question. I thought they looked very close visually based upon some on line pics

[Brad M.]

Re: What are differences between R79 and R89 batte

Thanks, that answered my question. I thought they looked very close visually based upon some on line pics