I run 8 quarts in the stock 74 pan with the bulltear external filter hung from the engine. No foaming, crank whipping, or any other issues even on very steep ascents and descents. It'd be real hard to run the pan dry too!
I didn't really trust the experiment done on AMC forums, I needed to know that it wasn't going to be above the baffle. So I set it up on the kitchen counter and added water until I was a sixteenth under the baffle of the pan. Pouring that into a measuring cup showed just over six quarts. So on first fire up I filled it to six quarts, put a quart in the filter, and ran the engine. With all of the break in lube, moly break in grease, and other crap in the oil it read just barely over full. I changed the oil, used the same procedure, and it read perfectly on the full line with the oil galleries full from the break in run. The stock fill line indicates five quarts in the pan, so from there I added another quart bringing my grand total to 8 quarts. Keep in mind that my aftermarket filter system (filter, adaptor, fittings, about 8 inches of 1/2" ID copper tubing) holds at least a quart and a half.
If I had to do it all again I would also plumb in a low flow restriction cooler for at least another quart and to keep the oil from heat soaking, and an acusump for additional capacity, pre lubeing, and reserve oil pressure.
The acusump (
https://www.pegasusautoracing.com/produ ... Ap7-8P8HAQ) and plumbing should add around 4 quarts and a cooler should add another two. Certainly, 14 quarts would be plenty overkill.
Gabe, "reformed" Jeep hoarder.