Originally Posted by james04si
My PO changed over to a battery with side posts that screw in vs the regular top posts and that's one of the few "upgrades" that I kept. We won't discuss the wooden shelf he built on the inside of the fender to set the battery on without holding it down at all. Only problem I have had was the wonderful Walmart employees that said a battery with side posts would never work in my jeep because the book didn't specify that battery.
"Side posts" are a GM "innovation" - done to help lower hoodlines, without having to lower the battery in the engine bay.
GM took a few years, but they figured out that side posts are difficult for a number of high-current applications - not enough cooling airflow over the terminal/pad assembly, and large engines or extensive high loads can heat the pads up to the point where they melt right out of the battery case!
Most battery manufacturers recommend a limit of 75A through the side posts pad for more than a few minutes, for that reason. (That, and lead melts at low temperatures.) The exception is Odyssey - I believe they use brass, nickel brass, or nickel-plated brass for their pads, I haven't checked. But, they say "No problem" - even for a winch! I haven't had a change to verify how or why.
Based on information gathered from Exide, International, Autolite, and Optima, I typically recommend using side posts for accessory distribution up to 75A constant-duty, up to about 200A for infrequent use (up to two minutes out of an hour,) and not for winching at all!
Starter motor loads for our beloved AMC sixes typically run 110-130A (no load) or 160-180A (cranking current.) Plan accordingly.