TAC Tech => Electrical => Topic started by: chief poncho on March 25, 2021, 04:51:11 PM

Title: Side post or top post battery preference?
Post by: chief poncho on March 25, 2021, 04:51:11 PM
Just curious.  I think I know the pros and cons of each.  Other than going with one of the repro side post batteries purely for aesthetic resto looks, is there any benefit to staying with a sidepost if you don't go with one of the expensive repros? 

Title: Re: Side post or top post battery preference?
Post by: Jack on March 26, 2021, 05:58:19 PM
I prefer top posts as you can get nice solid connections (more surface area). And they look better...
Title: Re: Side post or top post battery preference?
Post by: Gene-73 on March 26, 2021, 10:29:11 PM
If you go with an Optima battery, which there are good reasons to do, you can get dual posts on top AND side. This gives you additional connection points for all the extras we add to these old cars.
https://www.summitracing.com/parts/ult-9004-003 (https://www.summitracing.com/parts/ult-9004-003)
Title: Re: Side post or top post battery preference?
Post by: firebirdparts on March 27, 2021, 09:56:21 PM
I do like the way side posts attach.  You're not deforming anything.  FWIW.
Title: Re: Side post or top post battery preference?
Post by: JJ 109 on March 28, 2021, 03:48:16 PM
Don’t think it matters a lot.

I have top, but think sides a little cleaner looking
Title: Re: Side post or top post battery preference?
Post by: chief poncho on May 03, 2021, 05:31:52 PM
I ended up going with a sidepost.  I bought an Interstate battery at Costco.  I can buy a topper if I want it to look more original.  Has  a 3 year full replacement warranty too!   Sidepost just looks cleaner installed.
Title: Re: Side post or top post battery preference?
Post by: roadking77 on May 03, 2021, 06:25:41 PM
I have side post, the couple of times I have had to jump start has been a PIA. Top post may be easier for that. Other than that I dont suppose I have a preference either way.
Title: Re: Side post or top post battery preference?
Post by: 5th T/A on May 04, 2021, 04:04:09 PM
I don't think there is much advantage to one over the other. GM tried to push side post as a better technology, but even GM went back to top post. As mentioned the terminal connection has more surface area on a top post. Side post are easier to quickly disconnect or connect, all you need is a ratcheting 5/16" box wrench.

I think initially when batteries had vented caps the thought was side mount terminals were exposed to less gas and corrosion would be reduced. Shortly after side terminals GM introduced maintenance free batteries. I don't think they were much different than wet cell batteries of the day, but they eliminated the vent caps.

I believe AGM batteries are pretty common on cars today, they vent very little gas, pretty much reducing the issues with terminal corrosion. I went with an Optima AGM on my car for several reasons. Less gassing, corrosion and it has both side and top mount terminals. The manufacturer of my EFI system insists the ECU and CDI box get mounted directly to the battery and not to use buss bars or junctions before the battery. By using a dual terminal battery I was able to retain my original battery cables using the side terminals. The top terminals were open for my ECU and CDI box. If I ever have to go to electric fans I can also connect them to the top posts.

I plan to put insulating covers over the positive terminals, but haven't done so yet.

(https://live.staticflickr.com/65535/51157592182_42b89c47fc_k.jpg) (https://flic.kr/p/2kWC2Rq)IMG_8024 (https://flic.kr/p/2kWC2Rq) by Lawrence Alexander (https://www.flickr.com/photos/188552644@N06/), on Flickr
Title: Re: Side post or top post battery preference?
Post by: Jack on May 07, 2021, 10:10:49 AM
That's a nice setup that I've never seen before.
Title: Re: Side post or top post battery preference?
Post by: Meshuga T/A on May 09, 2021, 08:25:08 AM
Mike a topper, and you can get 5 versions now.   Nice detail under the hood. 
Title: Re: Side post or top post battery preference?
Post by: scarebird on May 09, 2021, 01:10:31 PM
Side post with one variable: I use 3/8" bolt eye cable connecters.

Run a 3/8-16 x 1 bolt with a nut threaded to the top by the bolt head thru the eye and into the battery.  Once the bolt is bottomed out, I then snug the nut down onto the eye.  Nothing to wear out, easy to remove/install and unlike GM's design will not loosen (they are noted for this).
Title: Re: Side post or top post battery preference?
Post by: twov8sandat4 on May 17, 2021, 07:13:19 AM
Has anyone relocated their battery to the trunk to shift some weight from the front?  In the process of replacing all my brake lines, and master cylinder, I had to remove the inner fenderwell to remove the last clip holding the front to rear brake line.  Which got me thinking, since the battery is out, would it make sense to relocate it to the rear?  This is not a drag car, just a nice driver with the future plan to take it to open track days.

Thanks.
Title: Re: Side post or top post battery preference?
Post by: scarebird on May 17, 2021, 03:51:43 PM
Yes, mine is in the passenger trunk.  LS' have the starter on the passenger side so routing is far easier.
Title: Re: Side post or top post battery preference?
Post by: jonathonar89 on May 17, 2021, 07:41:26 PM
I have always used side post because that is what all my vehicles have come with from the factory.  The times I've messed with top-post on other cars, I'll admit I have been a bit jealous. 

In either case, it's always about making a clean, solid and tight connection.  Both can act up if not properly installed/maintained.