I don't have a data logger. The only ones that I can afford, or are willing to spend money on, will only do up to 100A spec (120A real life), so I figured that there was no sense in getting one.

The 4S is enough for the bigish truck. I won't say that 5S or 6S wouldn't be better for more efficiency and less heat, but the 4S does fine. Considering the cost of lipo packs, I like to keep my battery configurations simple. Besides, I haven't yet found a controller that I like as much as the Mamba Max, and all that can comfortably do is 4S so that's what I run.

Keep in mind, if you are going to do one of these Muggys, there was work that NEEDED to be done. Not as a matter of preference, but really needed to be done. The stock steering is really sloppy and the chassis flexes A LOT. It think that's why I was flattening so many spur gears. I've been running the same spur in my buggy since I converted it about 6 weeks ago. I just did the Muggy and I'm on my 4th spur. I haven't had to change it since reinforcing the chassis.