Loose battery terminal
 

Went on a cruise today with the local go fast group. Had some fun. (Lambo kill in the record books) But at the last fuel stop the car wouldn't start. Discovered the positive terminal was loose. W/o closely inspecting I went looking for something to tighten it with. Luckily the convenience store had POS pliers for sale. Weapon in hand I headed the car ready to be triumphant. Stuck my fat head in the truck and got a good look. The terminal was as tight as it could go. And could still be lifted off the terminal. WTF?!?! After trying to think of ways to jerry rig it, I decided to just have the wife put a bit of downward pressure on the cable to see if that would do the trick. Bingo!

Now all that said...what are my choices? I've thought about a piece of paperclip to sheet metal to make shims. Is the only correct fix to re-terminate the cable?

You can shim it or you can replace the terminal end and/or battery.
Also, loosen it up and ensure that its seated all the way down then tighten it. Battery posts are tapered slightly.

That's a good thought. Thanks. The battery is nearly 6 years old though. Though still turns the starter pretty strong. It might be good insurance to just go ahead any change it. But I would wait until after winter. Don't see much use in buying a new battery to have it sit up for months.

Parts store had a battery post shim. Problem solved. Battery also tested in good shape.

In a pinch, I have removed a trim screw from the door sill plate & screwed it between the battery terminal & post to tighten it.

I'm a sucker for old, tired NA Miatas and have had more than a dozen take residence with me over the years. I'd say that the auto parts shim kit has been installed on 3-4 of 'em... Not sure why since nothing looks stretched or deformed on the Mazda cable end..?

BTW, the spirited run sounds like a blast. Poor Lambo owner. I guess he'll sell that car now or hide it behind a barn now that a Miata took his lunch money!